Using reconfigurable hardware to accelerate multiple sequence alignment with ClustalW.

PubMed

Oliver, Tim; Schmidt, Bertil; Nathan, Darran; Clemens, Ralf; Maskell, Douglas

2005-08-15

Aligning hundreds of sequences using progressive alignment tools such as ClustalW requires several hours on state-of-the-art workstations. We present a new approach to compute multiple sequence alignments in far shorter time using reconfigurable hardware. This results in an implementation of ClustalW with significant runtime savings on a standard off-the-shelf FPGA.

Microwave processing of a dental ceramic used in computer-aided design/computer-aided manufacturing.

PubMed

Pendola, Martin; Saha, Subrata

2015-01-01

Because of their favorable mechanical properties and natural esthetics, ceramics are widely used in restorative dentistry. The conventional ceramic sintering process required for their use is usually slow, however, and the equipment has an elevated energy consumption. Sintering processes that use microwaves have several advantages compared to regular sintering: shorter processing times, lower energy consumption, and the capacity for volumetric heating. The objective of this study was to test the mechanical properties of a dental ceramic used in computer-aided design/computer-aided manufacturing (CAD/CAM) after the specimens were processed with microwave hybrid sintering. Density, hardness, and bending strength were measured. When ceramic specimens were sintered with microwaves, the processing times were reduced and protocols were simplified. Hardness was improved almost 20% compared to regular sintering, and flexural strength measurements suggested that specimens were approximately 50% stronger than specimens sintered in a conventional system. Microwave hybrid sintering may preserve or improve the mechanical properties of dental ceramics designed for CAD/CAM processing systems, reducing processing and waiting times.

Turbulent transport measurements with a laser Doppler velocimeter

NASA Technical Reports Server (NTRS)

Edwards, R. V.; Angus, J. C.; Dunning, J. W., Jr.

1972-01-01

The power spectrum of phototube current from a laser Doppler velocimeter operating in the heterodyne mode has been computed. The spectrum is obtained in terms of the space time correlation function of the fluid. The spectral width and shape predicted by the theory are in agreement with experiment. For normal operating parameters the time average spectrum contains information only for times shorter than the Lagrangian integral time scale of the turbulence. To examine the long time behavior, one must use either extremely small scattering angles, much longer wavelength radiation or a different mode of signal analysis, e.g., FM detection.

Application-oriented offloading in heterogeneous networks for mobile cloud computing

NASA Astrophysics Data System (ADS)

Tseng, Fan-Hsun; Cho, Hsin-Hung; Chang, Kai-Di; Li, Jheng-Cong; Shih, Timothy K.

2018-04-01

Nowadays Internet applications have become more complicated that mobile device needs more computing resources for shorter execution time but it is restricted to limited battery capacity. Mobile cloud computing (MCC) is emerged to tackle the finite resource problem of mobile device. MCC offloads the tasks and jobs of mobile devices to cloud and fog environments by using offloading scheme. It is vital to MCC that which task should be offloaded and how to offload efficiently. In the paper, we formulate the offloading problem between mobile device and cloud data center and propose two algorithms based on application-oriented for minimum execution time, i.e. the Minimum Offloading Time for Mobile device (MOTM) algorithm and the Minimum Execution Time for Cloud data center (METC) algorithm. The MOTM algorithm minimizes offloading time by selecting appropriate offloading links based on application categories. The METC algorithm minimizes execution time in cloud data center by selecting virtual and physical machines with corresponding resource requirements of applications. Simulation results show that the proposed mechanism not only minimizes total execution time for mobile devices but also decreases their energy consumption.

Generalized activity equations for spiking neural network dynamics.

PubMed

Buice, Michael A; Chow, Carson C

2013-01-01

Much progress has been made in uncovering the computational capabilities of spiking neural networks. However, spiking neurons will always be more expensive to simulate compared to rate neurons because of the inherent disparity in time scales-the spike duration time is much shorter than the inter-spike time, which is much shorter than any learning time scale. In numerical analysis, this is a classic stiff problem. Spiking neurons are also much more difficult to study analytically. One possible approach to making spiking networks more tractable is to augment mean field activity models with some information about spiking correlations. For example, such a generalized activity model could carry information about spiking rates and correlations between spikes self-consistently. Here, we will show how this can be accomplished by constructing a complete formal probabilistic description of the network and then expanding around a small parameter such as the inverse of the number of neurons in the network. The mean field theory of the system gives a rate-like description. The first order terms in the perturbation expansion keep track of covariances.

Optimization and parallelization of the thermal–hydraulic subchannel code CTF for high-fidelity multi-physics applications

DOE PAGES

Salko, Robert K.; Schmidt, Rodney C.; Avramova, Maria N.

2014-11-23

This study describes major improvements to the computational infrastructure of the CTF subchannel code so that full-core, pincell-resolved (i.e., one computational subchannel per real bundle flow channel) simulations can now be performed in much shorter run-times, either in stand-alone mode or as part of coupled-code multi-physics calculations. These improvements support the goals of the Department Of Energy Consortium for Advanced Simulation of Light Water Reactors (CASL) Energy Innovation Hub to develop high fidelity multi-physics simulation tools for nuclear energy design and analysis.

Characterization and Computational Modeling of Minor Phases in Alloy LSHR

NASA Technical Reports Server (NTRS)

Jou, Herng-Jeng; Olson, Gregory; Gabb, Timothy; Garg, Anita; Miller, Derek

2012-01-01

The minor phases of powder metallurgy disk superalloy LSHR were studied. Samples were consistently heat treated at three different temperatures for long times to approach equilibrium. Additional heat treatments were also performed for shorter times, to assess minor phase kinetics in non-equilibrium conditions. Minor phases including MC carbides, M23C6 carbides, M3B2 borides, and sigma were identified. Their average sizes and total area fractions were determined. CALPHAD thermodynamics databases and PrecipiCalc(TradeMark), a computational precipitation modeling tool, were employed with Ni-base thermodynamics and diffusion databases to model and simulate the phase microstructural evolution observed in the experiments with an objective to identify the model limitations and the directions of model enhancement.

Sockets Manufactured by CAD/CAM Method Have Positive Effects on the Quality of Life of Patients With Transtibial Amputation.

PubMed

Karakoç, Mehmet; Batmaz, İbrahim; Sariyildiz, Mustafa Akif; Yazmalar, Levent; Aydin, Abdülkadir; Em, Serda

2017-08-01

Patients with amputation need prosthesis to comfortably move around. One of the most important parts of a good prosthesis is the socket. Currently, the most commonly used method is the traditional socket manufacturing method, which involves manual work; however, computer-aided design/computer-aided manufacturing (CAD/CAM) is also being used in the recent years. The present study aimed to investigate the effects of sockets manufactured by traditional and CAD/CAM method on clinical characteristics and quality of life of patients with transtibial amputation. The study included 72 patients with transtibial amputation using prosthesis, 36 of whom had CAD/CAM prosthetic sockets (group 1) and 36 had traditional prosthetic sockets (group 2). Amputation reason, prosthesis lifetime, walking time and distance with prosthesis, pain-free walking time with prosthesis, production time of the prosthesis, and adaptation time to the prosthesis were questioned. Quality of life was assessed using the 36-item Short Form Health Survey questionnaire and the Trinity Amputation and Prosthesis Experience Scales. Walking time and distance and pain-free walking time with prosthesis were significantly better in group 1 than those in group 2. Furthermore, the prosthesis was applied in a significantly shorter time, and socket adaptation time was significantly shorter in group 1. Except emotional role limitation, all 36-item Short Form Healthy Survey questionnaire parameters were significantly better in group 1 than in group 2. Trinity Amputation and Prosthesis Experience Scales activity limitation scores of group 1 were lower, and Trinity Amputation and Prosthesis Experience Scales satisfaction with the prosthesis scores were higher than those in group 2. Our study demonstrated that the sockets manufactured by CAD/CAM methods yield better outcomes in quality of life of patients with transtibial amputation than the sockets manufactured by the traditional method.

Fast Simulation of the Impact Parameter Calculation of Electrons through Pair Production

NASA Astrophysics Data System (ADS)

Bang, Hyesun; Kweon, MinJung; Huh, Kyoung Bum; Pachmayer, Yvonne

2018-05-01

A fast simulation method is introduced that reduces tremendously the time required for the impact parameter calculation, a key observable in physics analyses of high energy physics experiments and detector optimisation studies. The impact parameter of electrons produced through pair production was calculated considering key related processes using the Bethe-Heitler formula, the Tsai formula and a simple geometric model. The calculations were performed at various conditions and the results were compared with those from full GEANT4 simulations. The computation time using this fast simulation method is 104 times shorter than that of the full GEANT4 simulation.

An extraction algorithm of pulmonary fissures from multislice CT image

NASA Astrophysics Data System (ADS)

Tachibana, Hiroyuki; Saita, Shinsuke; Yasutomo, Motokatsu; Kubo, Mitsuru; Kawata, Yoshiki; Niki, Noboru; Nakano, Yasutaka; Sasagawa, Michizo; Eguchi, Kenji; Moriyama, Noriyuki

2005-04-01

Aging and smoking history increases number of pulmonary emphysema. Alveoli restoration destroyed by pulmonary emphysema is difficult and early direction is important. Multi-slice CT technology has been improving 3-D image analysis with higher body axis resolution and shorter scan time. And low-dose high accuracy scanning becomes available. Multi-slice CT image helps physicians with accurate measuring but huge volume of the image data takes time and cost. This paper is intended for computer added emphysema region analysis and proves effectiveness of proposed algorithm.

Expected Reachability-Time Games

NASA Astrophysics Data System (ADS)

Forejt, Vojtěch; Kwiatkowska, Marta; Norman, Gethin; Trivedi, Ashutosh

In an expected reachability-time game (ERTG) two players, Min and Max, move a token along the transitions of a probabilistic timed automaton, so as to minimise and maximise, respectively, the expected time to reach a target. These games are concurrent since at each step of the game both players choose a timed move (a time delay and action under their control), and the transition of the game is determined by the timed move of the player who proposes the shorter delay. A game is turn-based if at any step of the game, all available actions are under the control of precisely one player. We show that while concurrent ERTGs are not always determined, turn-based ERTGs are positionally determined. Using the boundary region graph abstraction, and a generalisation of Asarin and Maler's simple function, we show that the decision problems related to computing the upper/lower values of concurrent ERTGs, and computing the value of turn-based ERTGs are decidable and their complexity is in NEXPTIME ∩ co-NEXPTIME.

Soft tissue deformation estimation by spatio-temporal Kalman filter finite element method.

PubMed

Yarahmadian, Mehran; Zhong, Yongmin; Gu, Chengfan; Shin, Jaehyun

2018-01-01

Soft tissue modeling plays an important role in the development of surgical training simulators as well as in robot-assisted minimally invasive surgeries. It has been known that while the traditional Finite Element Method (FEM) promises the accurate modeling of soft tissue deformation, it still suffers from a slow computational process. This paper presents a Kalman filter finite element method to model soft tissue deformation in real time without sacrificing the traditional FEM accuracy. The proposed method employs the FEM equilibrium equation and formulates it as a filtering process to estimate soft tissue behavior using real-time measurement data. The model is temporally discretized using the Newmark method and further formulated as the system state equation. Simulation results demonstrate that the computational time of KF-FEM is approximately 10 times shorter than the traditional FEM and it is still as accurate as the traditional FEM. The normalized root-mean-square error of the proposed KF-FEM in reference to the traditional FEM is computed as 0.0116. It is concluded that the proposed method significantly improves the computational performance of the traditional FEM without sacrificing FEM accuracy. The proposed method also filters noises involved in system state and measurement data.

Management and Analysis of Biological and Clinical Data: How Computer Science May Support Biomedical and Clinical Research

NASA Astrophysics Data System (ADS)

Veltri, Pierangelo

The use of computer based solutions for data management in biology and clinical science has contributed to improve life-quality and also to gather research results in shorter time. Indeed, new algorithms and high performance computation have been using in proteomics and genomics studies for curing chronic diseases (e.g., drug designing) as well as supporting clinicians both in diagnosis (e.g., images-based diagnosis) and patient curing (e.g., computer based information analysis on information gathered from patient). In this paper we survey on examples of computer based techniques applied in both biology and clinical contexts. The reported applications are also results of experiences in real case applications at University Medical School of Catanzaro and also part of experiences of the National project Staywell SH 2.0 involving many research centers and companies aiming to study and improve citizen wellness.

Autocorrelated process control: Geometric Brownian Motion approach versus Box-Jenkins approach

NASA Astrophysics Data System (ADS)

Salleh, R. M.; Zawawi, N. I.; Gan, Z. F.; Nor, M. E.

2018-04-01

Existing of autocorrelation will bring a significant effect on the performance and accuracy of process control if the problem does not handle carefully. When dealing with autocorrelated process, Box-Jenkins method will be preferred because of the popularity. However, the computation of Box-Jenkins method is too complicated and challenging which cause of time-consuming. Therefore, an alternative method which known as Geometric Brownian Motion (GBM) is introduced to monitor the autocorrelated process. One real case of furnace temperature data is conducted to compare the performance of Box-Jenkins and GBM methods in monitoring autocorrelation process. Both methods give the same results in terms of model accuracy and monitoring process control. Yet, GBM is superior compared to Box-Jenkins method due to its simplicity and practically with shorter computational time.

Novel hybrid GPU-CPU implementation of parallelized Monte Carlo parametric expectation maximization estimation method for population pharmacokinetic data analysis.

PubMed

Ng, C M

2013-10-01

The development of a population PK/PD model, an essential component for model-based drug development, is both time- and labor-intensive. A graphical-processing unit (GPU) computing technology has been proposed and used to accelerate many scientific computations. The objective of this study was to develop a hybrid GPU-CPU implementation of parallelized Monte Carlo parametric expectation maximization (MCPEM) estimation algorithm for population PK data analysis. A hybrid GPU-CPU implementation of the MCPEM algorithm (MCPEMGPU) and identical algorithm that is designed for the single CPU (MCPEMCPU) were developed using MATLAB in a single computer equipped with dual Xeon 6-Core E5690 CPU and a NVIDIA Tesla C2070 GPU parallel computing card that contained 448 stream processors. Two different PK models with rich/sparse sampling design schemes were used to simulate population data in assessing the performance of MCPEMCPU and MCPEMGPU. Results were analyzed by comparing the parameter estimation and model computation times. Speedup factor was used to assess the relative benefit of parallelized MCPEMGPU over MCPEMCPU in shortening model computation time. The MCPEMGPU consistently achieved shorter computation time than the MCPEMCPU and can offer more than 48-fold speedup using a single GPU card. The novel hybrid GPU-CPU implementation of parallelized MCPEM algorithm developed in this study holds a great promise in serving as the core for the next-generation of modeling software for population PK/PD analysis.

Simple and Effective Algorithms: Computer-Adaptive Testing.

ERIC Educational Resources Information Center

Linacre, John Michael

Computer-adaptive testing (CAT) allows improved security, greater scoring accuracy, shorter testing periods, quicker availability of results, and reduced guessing and other undesirable test behavior. Simple approaches can be applied by the classroom teacher, or other content specialist, who possesses simple computer equipment and elementary…

Onboard Run-Time Goal Selection for Autonomous Operations

NASA Technical Reports Server (NTRS)

Rabideau, Gregg; Chien, Steve; McLaren, David

2010-01-01

We describe an efficient, online goal selection algorithm for use onboard spacecraft and its use for selecting goals at runtime. Our focus is on the re-planning that must be performed in a timely manner on the embedded system where computational resources are limited. In particular, our algorithm generates near optimal solutions to problems with fully specified goal requests that oversubscribe available resources but have no temporal flexibility. By using a fast, incremental algorithm, goal selection can be postponed in a "just-in-time" fashion allowing requests to be changed or added at the last minute. This enables shorter response cycles and greater autonomy for the system under control.

Recent advances in the reconstruction of cranio-maxillofacial defects using computer-aided design/computer-aided manufacturing.

PubMed

Oh, Ji-Hyeon

2018-12-01

With the development of computer-aided design/computer-aided manufacturing (CAD/CAM) technology, it has been possible to reconstruct the cranio-maxillofacial defect with more accurate preoperative planning, precise patient-specific implants (PSIs), and shorter operation times. The manufacturing processes include subtractive manufacturing and additive manufacturing and should be selected in consideration of the material type, available technology, post-processing, accuracy, lead time, properties, and surface quality. Materials such as titanium, polyethylene, polyetheretherketone (PEEK), hydroxyapatite (HA), poly-DL-lactic acid (PDLLA), polylactide-co-glycolide acid (PLGA), and calcium phosphate are used. Design methods for the reconstruction of cranio-maxillofacial defects include the use of a pre-operative model printed with pre-operative data, printing a cutting guide or template after virtual surgery, a model after virtual surgery printed with reconstructed data using a mirror image, and manufacturing PSIs by directly obtaining PSI data after reconstruction using a mirror image. By selecting the appropriate design method, manufacturing process, and implant material according to the case, it is possible to obtain a more accurate surgical procedure, reduced operation time, the prevention of various complications that can occur using the traditional method, and predictive results compared to the traditional method.

Sitting Time, Physical Activity and Sleep by Work Type and Pattern—The Australian Longitudinal Study on Women’s Health

PubMed Central

Clark, Bronwyn K.; Kolbe-Alexander, Tracy L.; Duncan, Mitch J.; Brown, Wendy

2017-01-01

Data from the Australian Longitudinal Study on Women’s Health were used to examine how work was associated with time spent sleeping, sitting and in physical activity (PA), in working women. Young (31–36 years; 2009) and mid-aged (59–64 years; 2010) women reported sleep (categorised as shorter ≤6 h/day and longer ≥8 h/day) and sitting time (work, transport, television, non-work computer, and other; summed for total sitting time) on the most recent work and non-work day; and moderate and vigorous PA (categorised as meeting/not meeting guidelines) in the previous week. Participants reported occupation (manager/professional; clerical/sales; trades/transport/labourer), work hours (part-time; full-time) and work pattern (shift/night; not shift/night). The odds of shorter sleep on work days was higher in both cohorts for women who worked shift or night hours. Longer sitting time on work days, made up primarily of sitting for work, was found for managers/professionals, clerical/sales and full-time workers. In the young cohort, clerical/sales workers and in the mid-aged cohort, full-time workers were less likely to meet PA guidelines. These results suggest multiple behaviour interventions tailored to work patterns and occupational category may be useful to improve the sleep, sitting and activity of working women. PMID:28287446

Sitting Time, Physical Activity and Sleep by Work Type and Pattern-The Australian Longitudinal Study on Women's Health.

PubMed

Clark, Bronwyn K; Kolbe-Alexander, Tracy L; Duncan, Mitch J; Brown, Wendy

2017-03-10

Data from the Australian Longitudinal Study on Women's Health were used to examine how work was associated with time spent sleeping, sitting and in physical activity (PA), in working women. Young (31-36 years; 2009) and mid-aged (59-64 years; 2010) women reported sleep (categorised as shorter ≤6 h/day and longer ≥8 h/day) and sitting time (work, transport, television, non-work computer, and other; summed for total sitting time) on the most recent work and non-work day; and moderate and vigorous PA (categorised as meeting/not meeting guidelines) in the previous week. Participants reported occupation (manager/professional; clerical/sales; trades/transport/labourer), work hours (part-time; full-time) and work pattern (shift/night; not shift/night). The odds of shorter sleep on work days was higher in both cohorts for women who worked shift or night hours. Longer sitting time on work days, made up primarily of sitting for work, was found for managers/professionals, clerical/sales and full-time workers. In the young cohort, clerical/sales workers and in the mid-aged cohort, full-time workers were less likely to meet PA guidelines. These results suggest multiple behaviour interventions tailored to work patterns and occupational category may be useful to improve the sleep, sitting and activity of working women.

Numerical Nuclear Second Derivatives on a Computing Grid: Enabling and Accelerating Frequency Calculations on Complex Molecular Systems.

PubMed

Yang, Tzuhsiung; Berry, John F

2018-06-04

The computation of nuclear second derivatives of energy, or the nuclear Hessian, is an essential routine in quantum chemical investigations of ground and transition states, thermodynamic calculations, and molecular vibrations. Analytic nuclear Hessian computations require the resolution of costly coupled-perturbed self-consistent field (CP-SCF) equations, while numerical differentiation of analytic first derivatives has an unfavorable 6 N ( N = number of atoms) prefactor. Herein, we present a new method in which grid computing is used to accelerate and/or enable the evaluation of the nuclear Hessian via numerical differentiation: NUMFREQ@Grid. Nuclear Hessians were successfully evaluated by NUMFREQ@Grid at the DFT level as well as using RIJCOSX-ZORA-MP2 or RIJCOSX-ZORA-B2PLYP for a set of linear polyacenes with systematically increasing size. For the larger members of this group, NUMFREQ@Grid was found to outperform the wall clock time of analytic Hessian evaluation; at the MP2 or B2LYP levels, these Hessians cannot even be evaluated analytically. We also evaluated a 156-atom catalytically relevant open-shell transition metal complex and found that NUMFREQ@Grid is faster (7.7 times shorter wall clock time) and less demanding (4.4 times less memory requirement) than an analytic Hessian. Capitalizing on the capabilities of parallel grid computing, NUMFREQ@Grid can outperform analytic methods in terms of wall time, memory requirements, and treatable system size. The NUMFREQ@Grid method presented herein demonstrates how grid computing can be used to facilitate embarrassingly parallel computational procedures and is a pioneer for future implementations.

Tractable Goal Selection with Oversubscribed Resources

NASA Technical Reports Server (NTRS)

Rabideau, Gregg; Chien, Steve; McLaren, David

2009-01-01

We describe an efficient, online goal selection algorithm and its use for selecting goals at runtime. Our focus is on the re-planning that must be performed in a timely manner on the embedded system where computational resources are limited. In particular, our algorithm generates near optimal solutions to problems with fully specified goal requests that oversubscribe available resources but have no temporal flexibility. By using a fast, incremental algorithm, goal selection can be postponed in a "just-in-time" fashion allowing requests to be changed or added at the last minute. This enables shorter response cycles and greater autonomy for the system under control.

Design of nucleic acid strands with long low-barrier folding pathways.

PubMed

Condon, Anne; Kirkpatrick, Bonnie; Maňuch, Ján

2017-01-01

A major goal of natural computing is to design biomolecules, such as nucleic acid sequences, that can be used to perform computations. We design sequences of nucleic acids that are "guaranteed" to have long folding pathways relative to their length. This particular sequences with high probability follow low-barrier folding pathways that visit a large number of distinct structures. Long folding pathways are interesting, because they demonstrate that natural computing can potentially support long and complex computations. Formally, we provide the first scalable designs of molecules whose low-barrier folding pathways, with respect to a simple, stacked pair energy model, grow superlinearly with the molecule length, but for which all significantly shorter alternative folding pathways have an energy barrier that is [Formula: see text] times that of the low-barrier pathway for any [Formula: see text] and a sufficiently long sequence.

A fast algorithm for vertex-frequency representations of signals on graphs

PubMed Central

Jestrović, Iva; Coyle, James L.; Sejdić, Ervin

2016-01-01

The windowed Fourier transform (short time Fourier transform) and the S-transform are widely used signal processing tools for extracting frequency information from non-stationary signals. Previously, the windowed Fourier transform had been adopted for signals on graphs and has been shown to be very useful for extracting vertex-frequency information from graphs. However, high computational complexity makes these algorithms impractical. We sought to develop a fast windowed graph Fourier transform and a fast graph S-transform requiring significantly shorter computation time. The proposed schemes have been tested with synthetic test graph signals and real graph signals derived from electroencephalography recordings made during swallowing. The results showed that the proposed schemes provide significantly lower computation time in comparison with the standard windowed graph Fourier transform and the fast graph S-transform. Also, the results showed that noise has no effect on the results of the algorithm for the fast windowed graph Fourier transform or on the graph S-transform. Finally, we showed that graphs can be reconstructed from the vertex-frequency representations obtained with the proposed algorithms. PMID:28479645

Estimation of time-series properties of gourd observed solar irradiance data using cloud properties derived from satellite observations

NASA Astrophysics Data System (ADS)

Watanabe, T.; Nohara, D.

2017-12-01

The shorter temporal scale variation in the downward solar irradiance at the ground level (DSI) is not understood well because researches in the shorter-scale variation in the DSI is based on the ground observation and ground observation stations are located coarsely. Use of dataset derived from satellite observation will overcome such defect. DSI data and MODIS cloud properties product are analyzed simultaneously. Three metrics: mean, standard deviation and sample entropy, are used to evaluate time-series properties of the DSI. Three metrics are computed from two-hours time-series centered at the observation time of MODIS over the ground observation stations. We apply the regression methods to design prediction models of each three metrics from cloud properties. The validation of the model accuracy show that mean and standard deviation are predicted with a higher degree of accuracy and that the accuracy of prediction of sample entropy, which represents the complexity of time-series, is not high. One of causes of lower prediction skill of sample entropy is the resolution of the MODIS cloud properties. Higher sample entropy is corresponding to the rapid fluctuation, which is caused by the small and unordered cloud. It seems that such clouds isn't retrieved well.

Real-Time Non-Intrusive Assessment of Viewing Distance during Computer Use.

PubMed

Argilés, Marc; Cardona, Genís; Pérez-Cabré, Elisabet; Pérez-Magrané, Ramon; Morcego, Bernardo; Gispets, Joan

2016-12-01

To develop and test the sensitivity of an ultrasound-based sensor to assess the viewing distance of visual display terminals operators in real-time conditions. A modified ultrasound sensor was attached to a computer display to assess viewing distance in real time. Sensor functionality was tested on a sample of 20 healthy participants while they conducted four 10-minute randomly presented typical computer tasks (a match-three puzzle game, a video documentary, a task requiring participants to complete a series of sentences, and a predefined internet search). The ultrasound sensor offered good measurement repeatability. Game, text completion, and web search tasks were conducted at shorter viewing distances (54.4 cm [95% CI 51.3-57.5 cm], 54.5 cm [95% CI 51.1-58.0 cm], and 54.5 cm [95% CI 51.4-57.7 cm], respectively) than the video task (62.3 cm [95% CI 58.9-65.7 cm]). Statistically significant differences were found between the video task and the other three tasks (all p < 0.05). Range of viewing distances (from 22 to 27 cm) was similar for all tasks (F = 0.996; p = 0.413). Real-time assessment of the viewing distance of computer users with a non-intrusive ultrasonic device disclosed a task-dependent pattern.

Dry eye syndrome among computer users

NASA Astrophysics Data System (ADS)

Gajta, Aurora; Turkoanje, Daniela; Malaescu, Iosif; Marin, Catalin-Nicolae; Koos, Marie-Jeanne; Jelicic, Biljana; Milutinovic, Vuk

2015-12-01

Dry eye syndrome is characterized by eye irritation due to changes of the tear film. Symptoms include itching, foreign body sensations, mucous discharge and transitory vision blurring. Less occurring symptoms include photophobia and eye tiredness. Aim of the work was to determine the quality of the tear film and ocular dryness potential risk in persons who spend more than 8 hours using computers and possible correlations between severity of symptoms (dry eyes symptoms anamnesis) and clinical signs assessed by: Schirmer test I, TBUT (Tears break-up time), TFT (Tear ferning test). The results show that subjects using computer have significantly shorter TBUT (less than 5 s for 56 % of subjects and less than 10 s for 37 % of subjects), TFT type II/III in 50 % of subjects and type III 31% of subjects was found when compared to computer non users (TFT type I and II was present in 85,71% of subjects). Visual display terminal use, more than 8 hours daily, has been identified as a significant risk factor for dry eye. It's been advised to all persons who spend substantial time using computers to use artificial tears drops in order to minimize the symptoms of dry eyes syndrome and prevents serious complications.

CAD Services: an Industry Standard Interface for Mechanical CAD Interoperability

NASA Technical Reports Server (NTRS)

Claus, Russell; Weitzer, Ilan

2002-01-01

Most organizations seek to design and develop new products in increasingly shorter time periods. At the same time, increased performance demands require a team-based multidisciplinary design process that may span several organizations. One approach to meet these demands is to use 'Geometry Centric' design. In this approach, design engineers team their efforts through one united representation of the design that is usually captured in a CAD system. Standards-based interfaces are critical to provide uniform, simple, distributed services that enable the 'Geometry Centric' design approach. This paper describes an industry-wide effort, under the Object Management Group's (OMG) Manufacturing Domain Task Force, to define interfaces that enable the interoperability of CAD, Computer Aided Manufacturing (CAM), and Computer Aided Engineering (CAE) tools. This critical link to enable 'Geometry Centric' design is called: Cad Services V1.0. This paper discusses the features of this standard and proposed application.

Comparative Investigation of Normal Modes and Molecular Dynamics of Hepatitis C NS5B Protein

NASA Astrophysics Data System (ADS)

Asafi, M. S.; Yildirim, A.; Tekpinar, M.

2016-04-01

Understanding dynamics of proteins has many practical implications in terms of finding a cure for many protein related diseases. Normal mode analysis and molecular dynamics methods are widely used physics-based computational methods for investigating dynamics of proteins. In this work, we studied dynamics of Hepatitis C NS5B protein with molecular dynamics and normal mode analysis. Principal components obtained from a 100 nanoseconds molecular dynamics simulation show good overlaps with normal modes calculated with a coarse-grained elastic network model. Coarse-grained normal mode analysis takes at least an order of magnitude shorter time. Encouraged by this good overlaps and short computation times, we analyzed further low frequency normal modes of Hepatitis C NS5B. Motion directions and average spatial fluctuations have been analyzed in detail. Finally, biological implications of these motions in drug design efforts against Hepatitis C infections have been elaborated.

Goal Selection for Embedded Systems with Oversubscribed Resources

NASA Technical Reports Server (NTRS)

Rabideau, Gregg; Chien, Steve; McLaren, David

2010-01-01

We describe an efficient, online goal selection algorithm and its use for selecting goals at runtime. Our focus is on the re-planning that must be performed in a timely manner on the embedded system where computational resources are limited. In particular, our algorithm generates near optimal solutions to problems with fully specified goal requests that oversubscribe available resources but have no temporal flexibility. By using a fast, incremental algorithm, goal selection can be postponed in a "just-in-time" fashion allowing requests to be changed or added at the last minute. This enables shorter response cycles and greater autonomy for the system under control.

A New Approach to Time-Resolved 3D-PTV

NASA Astrophysics Data System (ADS)

Boomsma, Aaron; Troolin, Dan; Bjorkquist, Dan; TSI Inc Team

2017-11-01

Volumetric three-component velocimetry via particle tracking is a powerful alternative to TomoPIV. It has been thoroughly documented that compared to TomoPIV, particle tracking velocimetry (PTV) methods (whether 2D or 3D) better resolve regions of high velocity gradient, identify fewer ghost particles, and are less computationally demanding, which results in shorter processing times. Recently, 3D-PTV has seen renewed interest in the PIV community with the availability of time-resolved data. Of course, advances in hardware are partly to thank for that availability-higher speed cameras, more effective memory management, and higher speed lasers. But in software, algorithms that utilize time resolved data to improve 3D particle reconstruction and particle tracking are also under development and advancing (e.g. shake-the-box, neighbor tracking reconstruction, etc.). .In the current study, we present a new 3D-PTV method that incorporates time-resolved data. We detail the method, its performance in terms of particle identification and reconstruction error and their relation to varying seeding densities, as well as computational performance.

Ensemble Sampling vs. Time Sampling in Molecular Dynamics Simulations of Thermal Conductivity

DOE PAGES

Gordiz, Kiarash; Singh, David J.; Henry, Asegun

2015-01-29

In this report we compare time sampling and ensemble averaging as two different methods available for phase space sampling. For the comparison, we calculate thermal conductivities of solid argon and silicon structures, using equilibrium molecular dynamics. We introduce two different schemes for the ensemble averaging approach, and show that both can reduce the total simulation time as compared to time averaging. It is also found that velocity rescaling is an efficient mechanism for phase space exploration. Although our methodology is tested using classical molecular dynamics, the ensemble generation approaches may find their greatest utility in computationally expensive simulations such asmore » first principles molecular dynamics. For such simulations, where each time step is costly, time sampling can require long simulation times because each time step must be evaluated sequentially and therefore phase space averaging is achieved through sequential operations. On the other hand, with ensemble averaging, phase space sampling can be achieved through parallel operations, since each ensemble is independent. For this reason, particularly when using massively parallel architectures, ensemble sampling can result in much shorter simulation times and exhibits similar overall computational effort.« less

Computationally efficient optimization of radiation drives

NASA Astrophysics Data System (ADS)

Zimmerman, George; Swift, Damian

2017-06-01

For many applications of pulsed radiation, the temporal pulse shape is designed to induce a desired time-history of conditions. This optimization is normally performed using multi-physics simulations of the system, adjusting the shape until the desired response is induced. These simulations may be computationally intensive, and iterative forward optimization is then expensive and slow. In principle, a simulation program could be modified to adjust the radiation drive automatically until the desired instantaneous response is achieved, but this may be impracticable in a complicated multi-physics program. However, the computational time increment is typically much shorter than the time scale of changes in the desired response, so the radiation intensity can be adjusted so that the response tends toward the desired value. This relaxed in-situ optimization method can give an adequate design for a pulse shape in a single forward simulation, giving a typical gain in computational efficiency of tens to thousands. This approach was demonstrated for the design of laser pulse shapes to induce ramp loading to high pressure in target assemblies where different components had significantly different mechanical impedance, requiring careful pulse shaping. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

Numerical Computation of Homogeneous Slope Stability

PubMed Central

Xiao, Shuangshuang; Li, Kemin; Ding, Xiaohua; Liu, Tong

2015-01-01

To simplify the computational process of homogeneous slope stability, improve computational accuracy, and find multiple potential slip surfaces of a complex geometric slope, this study utilized the limit equilibrium method to derive expression equations of overall and partial factors of safety. This study transformed the solution of the minimum factor of safety (FOS) to solving of a constrained nonlinear programming problem and applied an exhaustive method (EM) and particle swarm optimization algorithm (PSO) to this problem. In simple slope examples, the computational results using an EM and PSO were close to those obtained using other methods. Compared to the EM, the PSO had a small computation error and a significantly shorter computation time. As a result, the PSO could precisely calculate the slope FOS with high efficiency. The example of the multistage slope analysis indicated that this slope had two potential slip surfaces. The factors of safety were 1.1182 and 1.1560, respectively. The differences between these and the minimum FOS (1.0759) were small, but the positions of the slip surfaces were completely different than the critical slip surface (CSS). PMID:25784927

Numerical computation of homogeneous slope stability.

PubMed

Xiao, Shuangshuang; Li, Kemin; Ding, Xiaohua; Liu, Tong

2015-01-01

To simplify the computational process of homogeneous slope stability, improve computational accuracy, and find multiple potential slip surfaces of a complex geometric slope, this study utilized the limit equilibrium method to derive expression equations of overall and partial factors of safety. This study transformed the solution of the minimum factor of safety (FOS) to solving of a constrained nonlinear programming problem and applied an exhaustive method (EM) and particle swarm optimization algorithm (PSO) to this problem. In simple slope examples, the computational results using an EM and PSO were close to those obtained using other methods. Compared to the EM, the PSO had a small computation error and a significantly shorter computation time. As a result, the PSO could precisely calculate the slope FOS with high efficiency. The example of the multistage slope analysis indicated that this slope had two potential slip surfaces. The factors of safety were 1.1182 and 1.1560, respectively. The differences between these and the minimum FOS (1.0759) were small, but the positions of the slip surfaces were completely different than the critical slip surface (CSS).

Phase Transition of a Dynamical System with a Bi-Directional, Instantaneous Coupling to a Virtual System

NASA Astrophysics Data System (ADS)

Gintautas, Vadas; Hubler, Alfred

2006-03-01

As worldwide computer resources increase in power and decrease in cost, real-time simulations of physical systems are becoming increasingly prevalent, from laboratory models to stock market projections and entire ``virtual worlds'' in computer games. Often, these systems are meticulously designed to match real-world systems as closely as possible. We study the limiting behavior of a virtual horizontally driven pendulum coupled to its real-world counterpart, where the interaction occurs on a time scale that is much shorter than the time scale of the dynamical system. We find that if the physical parameters of the virtual system match those of the real system within a certain tolerance, there is a qualitative change in the behavior of the two-pendulum system as the strength of the coupling is increased. Applications include a new method to measure the physical parameters of a real system and the use of resonance spectroscopy to refine a computer model. As virtual systems better approximate real ones, even very weak interactions may produce unexpected and dramatic behavior. The research is supported by the National Science Foundation Grant No. NSF PHY 01-40179, NSF DMS 03-25939 ITR, and NSF DGE 03-38215.

Optimal Diabatic Dynamics of Majoarana-based Topological Qubits

NASA Astrophysics Data System (ADS)

Seradjeh, Babak; Rahmani, Armin; Franz, Marcel

In topological quantum computing, unitary operations on qubits are performed by adiabatic braiding of non-Abelian quasiparticles such as Majorana zero modes and are protected from local environmental perturbations. This scheme requires slow operations. By using the Pontryagin's maximum principle, here we show the same quantum gates can be implemented in much shorter times through optimal diabatic pulses. While our fast diabatic gates no not enjoy topological protection, they provide significant practical advantages due to their optimal speed and remarkable robustness to calibration errors and noise. NSERC, CIfAR, NSF DMR- 1350663, BSF 2014345.

Expert database system for quality control

NASA Astrophysics Data System (ADS)

Wang, Anne J.; Li, Zhi-Cheng

1993-09-01

There are more competitors today. Markets are not homogeneous they are fragmented into increasingly focused niches requiring greater flexibility in the product mix shorter manufacturing production runs and above allhigher quality. In this paper the author identified a real-time expert system as a way to improve plantwide quality management. The quality control expert database system (QCEDS) by integrating knowledge of experts in operations quality management and computer systems use all information relevant to quality managementfacts as well as rulesto determine if a product meets quality standards. Keywords: expert system quality control data base

A Computational Investigation of Sooting Limits of Spherical Diffusion Flames

NASA Technical Reports Server (NTRS)

Lecoustre, V. R.; Chao, B. H.; Sunderland, P. B.; Urban, D. L.; Stocker, D. P.; Axelbaum, R. L.

2007-01-01

Limiting conditions for soot particle inception in spherical diffusion flames were investigated numerically. The flames were modeled using a one-dimensional, time accurate diffusion flame code with detailed chemistry and transport and an optically thick radiation model. Seventeen normal and inverse flames were considered, covering a wide range of stoichiometric mixture fraction, adiabatic flame temperature, and residence time. These flames were previously observed to reach their sooting limits after 2 s of microgravity. Sooting-limit diffusion flames with residence times longer than 200 ms were found to have temperatures near 1190 K where C/O = 0.6, whereas flames with shorter residence times required increased temperatures. Acetylene was found to be a reasonable surrogate for soot precursor species in these flames, having peak mole fractions of about 0.01.

Multi-period project portfolio selection under risk considerations and stochastic income

NASA Astrophysics Data System (ADS)

Tofighian, Ali Asghar; Moezzi, Hamid; Khakzar Barfuei, Morteza; Shafiee, Mahmood

2018-02-01

This paper deals with multi-period project portfolio selection problem. In this problem, the available budget is invested on the best portfolio of projects in each period such that the net profit is maximized. We also consider more realistic assumptions to cover wider range of applications than those reported in previous studies. A novel mathematical model is presented to solve the problem, considering risks, stochastic incomes, and possibility of investing extra budget in each time period. Due to the complexity of the problem, an effective meta-heuristic method hybridized with a local search procedure is presented to solve the problem. The algorithm is based on genetic algorithm (GA), which is a prominent method to solve this type of problems. The GA is enhanced by a new solution representation and well selected operators. It also is hybridized with a local search mechanism to gain better solution in shorter time. The performance of the proposed algorithm is then compared with well-known algorithms, like basic genetic algorithm (GA), particle swarm optimization (PSO), and electromagnetism-like algorithm (EM-like) by means of some prominent indicators. The computation results show the superiority of the proposed algorithm in terms of accuracy, robustness and computation time. At last, the proposed algorithm is wisely combined with PSO to improve the computing time considerably.

[Rapid 3-Dimensional Models of Cerebral Aneurysm for Emergency Surgical Clipping].

PubMed

Konno, Takehiko; Mashiko, Toshihiro; Oguma, Hirofumi; Kaneko, Naoki; Otani, Keisuke; Watanabe, Eiju

2016-08-01

We developed a method for manufacturing solid models of cerebral aneurysms, with a shorter printing time than that involved in conventional methods, using a compact 3D printer with acrylonitrile-butadiene-styrene(ABS)resin. We further investigated the application and utility of this printing system in emergency clipping surgery. A total of 16 patients diagnosed with acute subarachnoid hemorrhage resulting from cerebral aneurysm rupture were enrolled in the present study. Emergency clipping was performed on the day of hospitalization. Digital Imaging and Communication in Medicine(DICOM)data obtained from computed tomography angiography(CTA)scans were edited and converted to stereolithography(STL)file formats, followed by the production of 3D models of the cerebral aneurysm by using the 3D printer. The mean time from hospitalization to the commencement of surgery was 242 min, whereas the mean time required for manufacturing the 3D model was 67 min. The average cost of each 3D model was 194 Japanese Yen. The time required for manufacturing the 3D models shortened to approximately 1 hour with increasing experience of producing 3D models. Favorable impressions for the use of the 3D models in clipping were reported by almost all neurosurgeons included in this study. Although 3D printing is often considered to involve huge costs and long manufacturing time, the method used in the present study requires shorter time and lower costs than conventional methods for manufacturing 3D cerebral aneurysm models, thus making it suitable for use in emergency clipping.

First-principles simulations of heat transport

NASA Astrophysics Data System (ADS)

Puligheddu, Marcello; Gygi, Francois; Galli, Giulia

2017-11-01

Advances in understanding heat transport in solids were recently reported by both experiment and theory. However an efficient and predictive quantum simulation framework to investigate thermal properties of solids, with the same complexity as classical simulations, has not yet been developed. Here we present a method to compute the thermal conductivity of solids by performing ab initio molecular dynamics at close to equilibrium conditions, which only requires calculations of first-principles trajectories and atomic forces, thus avoiding direct computation of heat currents and energy densities. In addition the method requires much shorter sequential simulation times than ordinary molecular dynamics techniques, making it applicable within density functional theory. We discuss results for a representative oxide, MgO, at different temperatures and for ordered and nanostructured morphologies, showing the performance of the method in different conditions.

Times to pain relief and pain freedom with rizatriptan 10 mg and other oral triptans

PubMed Central

Ng-Mak, D S; Hu, X H; Chen, Y; Ma, L; Solomon, G

2007-01-01

Background: In the clinical trial setting, oral rizatriptan 10 mg has greater efficacy than other oral triptans in freedom from migraine headache pain 2 h after dosing. Objective: The study objective is to compare the effectiveness of rizatriptan 10 mg and other oral triptans for acute migraine attack in a naturalistic setting. Methods: A total of 673 patients took rizatriptan 10 mg or their usual-care oral triptans for two migraine attacks in a sequential, cross-over manner and recorded outcomes using a diary and a stopwatch. Mean and median times to pain relief (PR) and pain freedom (PF) for rizatriptan and other oral triptans were compared. The effect of rizatriptan on times to PR and PF, adjusting for potential confounding factors (treatment sequence, treatment order and use of rescue medication), was computed via a Cox proportional hazard model. Results: Significantly, more patients taking rizatriptan achieved both PR and PF within 2 h after dosing than other oral triptans. Times to PR and PF were shorter with rizatriptan than with other oral triptans (median time to PR: 45 vs. 52 min, p < 0.0001; median time to PF: 100 vs. 124 min, p < 0.0001). The adjusted proportional hazard ratios (rizatriptan vs. other oral triptans) for times to PR and PF were 1.32 (95% CI: 1.22–1.44) and 1.27 (95% CI: 1.16–1.39) respectively. Conclusion: The times to PR and PF in a ‘naturalistic’ setting were significantly shorter for patients treating a migraine attack with rizatriptan 10 mg than with other oral triptans. PMID:17537184

78 FR 63946 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Revisions to Headboat Reporting...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-10-25

... electronically (via computer or internet) on a weekly basis or at intervals shorter than a week if notified by the NMFS' Southeast Fisheries Science Center (SEFSC) Science and Research Director (SRD), and would... regulations to explicitly require that headboats submit their fishing information electronically (via computer...

Non-Deterministic Dynamic Instability of Composite Shells

NASA Technical Reports Server (NTRS)

Chamis, Christos C.; Abumeri, Galib H.

2004-01-01

A computationally effective method is described to evaluate the non-deterministic dynamic instability (probabilistic dynamic buckling) of thin composite shells. The method is a judicious combination of available computer codes for finite element, composite mechanics, and probabilistic structural analysis. The solution method is incrementally updated Lagrangian. It is illustrated by applying it to thin composite cylindrical shell subjected to dynamic loads. Both deterministic and probabilistic buckling loads are evaluated to demonstrate the effectiveness of the method. A universal plot is obtained for the specific shell that can be used to approximate buckling loads for different load rates and different probability levels. Results from this plot show that the faster the rate, the higher the buckling load and the shorter the time. The lower the probability, the lower is the buckling load for a specific time. Probabilistic sensitivity results show that the ply thickness, the fiber volume ratio and the fiber longitudinal modulus, dynamic load and loading rate are the dominant uncertainties, in that order.

Dynamic Probabilistic Instability of Composite Structures

NASA Technical Reports Server (NTRS)

Chamis, Christos C.

2009-01-01

A computationally effective method is described to evaluate the non-deterministic dynamic instability (probabilistic dynamic buckling) of thin composite shells. The method is a judicious combination of available computer codes for finite element, composite mechanics and probabilistic structural analysis. The solution method is incrementally updated Lagrangian. It is illustrated by applying it to thin composite cylindrical shell subjected to dynamic loads. Both deterministic and probabilistic buckling loads are evaluated to demonstrate the effectiveness of the method. A universal plot is obtained for the specific shell that can be used to approximate buckling loads for different load rates and different probability levels. Results from this plot show that the faster the rate, the higher the buckling load and the shorter the time. The lower the probability, the lower is the buckling load for a specific time. Probabilistic sensitivity results show that the ply thickness, the fiber volume ratio and the fiber longitudinal modulus, dynamic load and loading rate are the dominant uncertainties in that order.

Split delivery vehicle routing problem with time windows: a case study

NASA Astrophysics Data System (ADS)

Latiffianti, E.; Siswanto, N.; Firmandani, R. A.

2018-04-01

This paper aims to implement an extension of VRP so called split delivery vehicle routing problem (SDVRP) with time windows in a case study involving pickups and deliveries of workers from several points of origin and several destinations. Each origin represents a bus stop and the destination represents either site or office location. An integer linear programming of the SDVRP problem is presented. The solution was generated using three stages of defining the starting points, assigning busses, and solving the SDVRP with time windows using an exact method. Although the overall computational time was relatively lengthy, the results indicated that the produced solution was better than the existing routing and scheduling that the firm used. The produced solution was also capable of reducing fuel cost by 9% that was obtained from shorter total distance travelled by the shuttle buses.

Association between coagulation function and patients with primary angle closure glaucoma: a 5-year retrospective case-control study.

PubMed

Li, Shengjie; Gao, Yanting; Shao, Mingxi; Tang, Binghua; Cao, Wenjun; Sun, Xinghuai

2017-11-04

To evaluate the association between coagulation function and patients with primary angle closure glaucoma (PACG). A retrospective, hospital-based, case-control study. Shanghai, China. A total of 1778 subjects were recruited from the Eye & ENT Hospital of Fudan University from January 2010 to December 2015, including patients with PACG (male=296; female=569) and control subjects (male=290; female=623). Sociodemographic data and clinical data were collected. The one-way analysis of variance test was used to compare the levels of laboratory parameters among the mild, moderate and severe PACG groups. Multivariate logistic regression analyses were performed to identify the independent risk factors for PACG. The nomogram was constructed based on the logistic regression model using the R project for statistical computing (R V.3.3.2). The activated partial thromboplastin time (APTT) of the PACG group was approximately 4% shorter (p<0.001) than that of the control group. The prothrombin time (PT) was approximately 2.40% shorter (p<0.001) in patients with PACG compared with the control group. The thrombin time was also approximately 2.14% shorter (p<0.001) in patients with PACG compared with the control group. The level of D-dimer was significantly higher (p=0.042) in patients with PACG. Moreover, the mean platelet volume (MPV) of the PACG group was significantly higher (p=0.013) than that of the control group. A similar trend was observed when coagulation parameters were compared between the PACG and control groups with respect to gender and/or age. Multiple logistic regression analyses revealed that APTT (OR=1.032, 95% CI 1.000 to 1.026), PT (OR=1.249, 95% CI 1.071 to 1.457) and MPV (OR=1.185, 95% CI 1.081 to 1.299) were independently associated with PACG. Patients with PACG had a shorter coagulation time. Our results suggest that coagulation function is significantly associated with patients with PACG and may play an important role in the onset and development of PACG. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Simulation optimization of PSA-threshold based prostate cancer screening policies

PubMed Central

Zhang, Jingyu; Denton, Brian T.; Shah, Nilay D.; Inman, Brant A.

2013-01-01

We describe a simulation optimization method to design PSA screening policies based on expected quality adjusted life years (QALYs). Our method integrates a simulation model in a genetic algorithm which uses a probabilistic method for selection of the best policy. We present computational results about the efficiency of our algorithm. The best policy generated by our algorithm is compared to previously recommended screening policies. Using the policies determined by our model, we present evidence that patients should be screened more aggressively but for a shorter length of time than previously published guidelines recommend. PMID:22302420

Accelerate Healthcare Data Analytics: An Agile Practice to Perform Collaborative and Reproducible Analyses.

PubMed

Hao, Bibo; Sun, Wen; Yu, Yiqin; Li, Jing; Hu, Gang; Xie, Guotong

2016-01-01

Recent advances in cloud computing and machine learning made it more convenient for researchers to gain insights from massive healthcare data, while performing analyses on healthcare data in current practice still lacks efficiency for researchers. What's more, collaborating among different researchers and sharing analysis results are challenging issues. In this paper, we developed a practice to make analytics process collaborative and analysis results reproducible by exploiting and extending Jupyter Notebook. After applying this practice in our use cases, we can perform analyses and deliver results with less efforts in shorter time comparing to our previous practice.

Stapled haemorrhoidopexy for the treatment of haemorrhoids: a systematic review.

PubMed

Burch, J; Epstein, D; Sari, A Baba-Akbari; Weatherly, H; Jayne, D; Fox, D; Woolacott, N

2009-03-01

This systematic review aimed to evaluate the short- and long-term safety, efficacy and costs of stapled haemorrhoidopexy (SH) compared with conventional haemorrhoidectomy. We searched 26 electronic databases and websites for studies in any language up to July 2006. Inclusion criteria were predefined, and each stage of the review process was conducted in duplicate. Twenty-seven randomized controlled trials were included (n = 2279). All had some methodological flaws. Postoperatively, 19 trials (95%) reported less pain, 17 (89%) reported a shorter operating time, 14 (88%) a shorter hospital stay, and 14 (93%) a shorter convalescence time following SH. However, prolapse was significantly more common after SH (OR 3.38; 95% CI: 1.00, 11.47). In the longer term, prolapse was significantly more common after SH (OR 4.34; 95% CI: 1.67, 11.28) as was reintervention for prolapse (OR 6.78; 95% CI: 2.00, 23.00). There were no differences in the rate or type of complications. Conventional haemorrhoidectomy and SH had similar costs during the initial admission. Compared with conventional haemorrhoidectomy, SH resulted in less postoperative pain, shorter operating time, a shorter hospital stay, and a shorter convalescence, but a higher rate of prolapse and reintervention for prolapse.

Computer games and fine motor skills.

PubMed

Borecki, Lukasz; Tolstych, Katarzyna; Pokorski, Mieczyslaw

2013-01-01

The study seeks to determine the influence of computer games on fine motor skills in young adults, an area of incomplete understanding and verification. We hypothesized that computer gaming could have a positive influence on basic motor skills, such as precision, aiming, speed, dexterity, or tremor. We examined 30 habitual game users (F/M - 3/27; age range 20-25 years) of the highly interactive game Counter Strike, in which players impersonate soldiers on a battlefield, and 30 age- and gender-matched subjects who declared never to play games. Selected tests from the Vienna Test System were used to assess fine motor skills and tremor. The results demonstrate that the game users scored appreciably better than the control subjects in all tests employed. In particular, the players did significantly better in the precision of arm-hand movements, as expressed by a lower time of errors, 1.6 ± 0.6 vs. 2.8 ± 0.6 s, a lower error rate, 13.6 ± 0.3 vs. 20.4 ± 2.2, and a shorter total time of performing a task, 14.6 ± 2.9 vs. 32.1 ± 4.5 s in non-players, respectively; p < 0.001 all. The findings demonstrate a positive influence of computer games on psychomotor functioning. We submit that playing computer games may be a useful training tool to increase fine motor skills and movement coordination.

Comparison of conventional ultrasonography and ultrasonography-computed tomography fusion imaging for target identification using digital/real hybrid phantoms: a preliminary study.

PubMed

Soyama, Takeshi; Sakuhara, Yusuke; Kudo, Kohsuke; Abo, Daisuke; Wang, Jeff; Ito, Yoichi M; Hasegawa, Yu; Shirato, Hiroki

2016-07-01

This preliminary study compared ultrasonography-computed tomography (US-CT) fusion imaging and conventional ultrasonography (US) for accuracy and time required for target identification using a combination of real phantoms and sets of digitally modified computed tomography (CT) images (digital/real hybrid phantoms). In this randomized prospective study, 27 spheres visible on B-mode US were placed at depths of 3.5, 8.5, and 13.5 cm (nine spheres each). All 27 spheres were digitally erased from the CT images, and a radiopaque sphere was digitally placed at each of the 27 locations to create 27 different sets of CT images. Twenty clinicians were instructed to identify the sphere target using US alone and fusion imaging. The accuracy of target identification of the two methods was compared using McNemar's test. The mean time required for target identification and error distances were compared using paired t tests. At all three depths, target identification was more accurate and the mean time required for target identification was significantly less with US-CT fusion imaging than with US alone, and the mean error distances were also shorter with US-CT fusion imaging. US-CT fusion imaging was superior to US alone in terms of accurate and rapid identification of target lesions.

Self-motion perception compresses time experienced in return travel.

PubMed

Seno, Takeharu; Ito, Hiroyuki; Shoji, Sunaga

2011-01-01

It is often anecdotally reported that time experienced in return travel (back to the start point) seems shorter than time spent in outward travel (travel to a new destination). Here, we report the first experimental results showing that return travel time is experienced as shorter than the actual time. This discrepancy is induced by the existence of self-motion perception.

The Use of Laser Guidance Reduces Fluoroscopy Time for C-Arm Cone-Beam Computed Tomography-Guided Biopsies

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

Kroes, Maarten W., E-mail: Maarten.Kroes@radboudumc.nl; Strijen, Marco J. L. van, E-mail: m.van.strijen@antoniusziekenhuis.nl; Braak, Sicco J., E-mail: sjbraak@gmail.com

2016-09-15

PurposeWhen using laser guidance for cone-beam computed tomography (CBCT)-guided needle interventions, planned needle paths are visualized to the operator without the need to switch between entry- and progress-view during needle placement. The current study assesses the effect of laser guidance during CBCT-guided biopsies on fluoroscopy and procedure times.Materials and MethodsProspective data from 15 CBCT-guided biopsies of 8–65 mm thoracic and abdominal lesions assisted by a ceiling-mounted laser guidance technique were compared to retrospective data of 36 performed CBCT-guided biopsies of lesions >20 mm using the freehand technique. Fluoroscopy time, procedure time, and number of CBCT-scans were recorded. All data are presented asmore » median (ranges).ResultsFor biopsies using the freehand technique, more fluoroscopy time was necessary to guide the needle onto the target, 165 s (83–333 s) compared to 87 s (44–190 s) for laser guidance (p < 0.001). Procedure times were shorter for freehand-guided biopsies, 24 min versus 30 min for laser guidance (p < 0.001).ConclusionThe use of laser guidance during CBCT-guided biopsies significantly reduces fluoroscopy time.« less

Challenges and opportunities of cloud computing for atmospheric sciences

NASA Astrophysics Data System (ADS)

Pérez Montes, Diego A.; Añel, Juan A.; Pena, Tomás F.; Wallom, David C. H.

2016-04-01

Cloud computing is an emerging technological solution widely used in many fields. Initially developed as a flexible way of managing peak demand it has began to make its way in scientific research. One of the greatest advantages of cloud computing for scientific research is independence of having access to a large cyberinfrastructure to fund or perform a research project. Cloud computing can avoid maintenance expenses for large supercomputers and has the potential to 'democratize' the access to high-performance computing, giving flexibility to funding bodies for allocating budgets for the computational costs associated with a project. Two of the most challenging problems in atmospheric sciences are computational cost and uncertainty in meteorological forecasting and climate projections. Both problems are closely related. Usually uncertainty can be reduced with the availability of computational resources to better reproduce a phenomenon or to perform a larger number of experiments. Here we expose results of the application of cloud computing resources for climate modeling using cloud computing infrastructures of three major vendors and two climate models. We show how the cloud infrastructure compares in performance to traditional supercomputers and how it provides the capability to complete experiments in shorter periods of time. The monetary cost associated is also analyzed. Finally we discuss the future potential of this technology for meteorological and climatological applications, both from the point of view of operational use and research.

Predictors of shorter sleep in early childhood

PubMed Central

McDonald, Laura; Wardle, Jane; Llewellyn, Clare H.; van Jaarsveld, Cornelia H.M.; Fisher, Abigail

2014-01-01

Objective The aim of this study was to identify socio-demographic and home environmental predictors of shorter sleep in early childhood, and to examine whether effects were mediated by the timing of bedtime or wake time. Methods Participants were from Gemini, a British birth cohort of twins, and included 1702 children; one randomly selected from each twin pair. Parents reported night-time sleep duration at an average age of 15.8 months (range 14–27 months) using a modified version of the Brief Infant Sleep Questionnaire. Multiple logistic regression models were used to identify predictors of shorter sleep for this study. Results Using a cut-off of <11 h a night, shorter sleep was reported in 14.1% of children. Lower maternal education, non-white ethnic background, being male, low birth weight, living in a home with >1 older child and watching >1 h of TV in the evening were independently associated with shorter sleep. Mediation analyses showed that associations between education, ethnicity, evening TV viewing and sleep were driven predominantly by later bedtimes, while sex differences were driven predominantly by earlier wake times in boys. Conclusion In this sample, multiple environmental factors were associated with shorter sleep in young children, with several operating predominantly through later bedtime. An emphasis on the importance of an early and consistent bedtime could help promote healthy sleep and reduce inequalities in child health. PMID:24726571

A Secure and Efficient Audit Mechanism for Dynamic Shared Data in Cloud Storage

PubMed Central

2014-01-01

With popularization of cloud services, multiple users easily share and update their data through cloud storage. For data integrity and consistency in the cloud storage, the audit mechanisms were proposed. However, existing approaches have some security vulnerabilities and require a lot of computational overheads. This paper proposes a secure and efficient audit mechanism for dynamic shared data in cloud storage. The proposed scheme prevents a malicious cloud service provider from deceiving an auditor. Moreover, it devises a new index table management method and reduces the auditing cost by employing less complex operations. We prove the resistance against some attacks and show less computation cost and shorter time for auditing when compared with conventional approaches. The results present that the proposed scheme is secure and efficient for cloud storage services managing dynamic shared data. PMID:24959630

A model for the accurate computation of the lateral scattering of protons in water

NASA Astrophysics Data System (ADS)

Bellinzona, E. V.; Ciocca, M.; Embriaco, A.; Ferrari, A.; Fontana, A.; Mairani, A.; Parodi, K.; Rotondi, A.; Sala, P.; Tessonnier, T.

2016-02-01

A pencil beam model for the calculation of the lateral scattering in water of protons for any therapeutic energy and depth is presented. It is based on the full Molière theory, taking into account the energy loss and the effects of mixtures and compounds. Concerning the electromagnetic part, the model has no free parameters and is in very good agreement with the FLUKA Monte Carlo (MC) code. The effects of the nuclear interactions are parametrized with a two-parameter tail function, adjusted on MC data calculated with FLUKA. The model, after the convolution with the beam and the detector response, is in agreement with recent proton data in water from HIT. The model gives results with the same accuracy of the MC codes based on Molière theory, with a much shorter computing time.

3D-printed guiding templates for improved osteosarcoma resection

NASA Astrophysics Data System (ADS)

Ma, Limin; Zhou, Ye; Zhu, Ye; Lin, Zefeng; Wang, Yingjun; Zhang, Yu; Xia, Hong; Mao, Chuanbin

2016-03-01

Osteosarcoma resection is challenging due to the variable location of tumors and their proximity with surrounding tissues. It also carries a high risk of postoperative complications. To overcome the challenge in precise osteosarcoma resection, computer-aided design (CAD) was used to design patient-specific guiding templates for osteosarcoma resection on the basis of the computer tomography (CT) scan and magnetic resonance imaging (MRI) of the osteosarcoma of human patients. Then 3D printing technique was used to fabricate the guiding templates. The guiding templates were used to guide the osteosarcoma surgery, leading to more precise resection of the tumorous bone and the implantation of the bone implants, less blood loss, shorter operation time and reduced radiation exposure during the operation. Follow-up studies show that the patients recovered well to reach a mean Musculoskeletal Tumor Society score of 27.125.

A secure and efficient audit mechanism for dynamic shared data in cloud storage.

PubMed

Kwon, Ohmin; Koo, Dongyoung; Shin, Yongjoo; Yoon, Hyunsoo

2014-01-01

With popularization of cloud services, multiple users easily share and update their data through cloud storage. For data integrity and consistency in the cloud storage, the audit mechanisms were proposed. However, existing approaches have some security vulnerabilities and require a lot of computational overheads. This paper proposes a secure and efficient audit mechanism for dynamic shared data in cloud storage. The proposed scheme prevents a malicious cloud service provider from deceiving an auditor. Moreover, it devises a new index table management method and reduces the auditing cost by employing less complex operations. We prove the resistance against some attacks and show less computation cost and shorter time for auditing when compared with conventional approaches. The results present that the proposed scheme is secure and efficient for cloud storage services managing dynamic shared data.

A model for the accurate computation of the lateral scattering of protons in water.

PubMed

Bellinzona, E V; Ciocca, M; Embriaco, A; Ferrari, A; Fontana, A; Mairani, A; Parodi, K; Rotondi, A; Sala, P; Tessonnier, T

2016-02-21

A pencil beam model for the calculation of the lateral scattering in water of protons for any therapeutic energy and depth is presented. It is based on the full Molière theory, taking into account the energy loss and the effects of mixtures and compounds. Concerning the electromagnetic part, the model has no free parameters and is in very good agreement with the FLUKA Monte Carlo (MC) code. The effects of the nuclear interactions are parametrized with a two-parameter tail function, adjusted on MC data calculated with FLUKA. The model, after the convolution with the beam and the detector response, is in agreement with recent proton data in water from HIT. The model gives results with the same accuracy of the MC codes based on Molière theory, with a much shorter computing time.

A glacier runoff extension to the Precipitation Runoff Modeling System

USGS Publications Warehouse

Van Beusekom, Ashley E.; Viger, Roland

2016-01-01

A module to simulate glacier runoff, PRMSglacier, was added to PRMS (Precipitation Runoff Modeling System), a distributed-parameter, physical-process hydrological simulation code. The extension does not require extensive on-glacier measurements or computational expense but still relies on physical principles over empirical relations as much as is feasible while maintaining model usability. PRMSglacier is validated on two basins in Alaska, Wolverine, and Gulkana Glacier basin, which have been studied since 1966 and have a substantial amount of data with which to test model performance over a long period of time covering a wide range of climatic and hydrologic conditions. When error in field measurements is considered, the Nash-Sutcliffe efficiencies of streamflow are 0.87 and 0.86, the absolute bias fractions of the winter mass balance simulations are 0.10 and 0.08, and the absolute bias fractions of the summer mass balances are 0.01 and 0.03, all computed over 42 years for the Wolverine and Gulkana Glacier basins, respectively. Without taking into account measurement error, the values are still within the range achieved by the more computationally expensive codes tested over shorter time periods.

Identifying high frequency signals in the daily swath mascon solutions from GRACE

NASA Astrophysics Data System (ADS)

Save, H.

2016-12-01

The Gravity Recovery and Climate Experiment (GRACE) mission has provided us with unique information about the total water column in the Earth system over the past 14 years. The GRACE project provides a monthly mean time-variable gravity solution. There has been significant progress in the community over the years to develop shorter time-window gravity solutions. The daily swath mascon solutions, which are under development at the Center for Space Research (CSR), are computed using daily GRACE observation data. This paper discusses the development and the progress of this product. This paper summarizes the analysis of these solutions with special emphasis on identifying the higher frequency natural processes observed by GRACE using these daily swath mascon solutions.

Application of Dynamic Analysis in Semi-Analytical Finite Element Method.

PubMed

Liu, Pengfei; Xing, Qinyan; Wang, Dawei; Oeser, Markus

2017-08-30

Analyses of dynamic responses are significantly important for the design, maintenance and rehabilitation of asphalt pavement. In order to evaluate the dynamic responses of asphalt pavement under moving loads, a specific computational program, SAFEM, was developed based on a semi-analytical finite element method. This method is three-dimensional and only requires a two-dimensional FE discretization by incorporating Fourier series in the third dimension. In this paper, the algorithm to apply the dynamic analysis to SAFEM was introduced in detail. Asphalt pavement models under moving loads were built in the SAFEM and commercial finite element software ABAQUS to verify the accuracy and efficiency of the SAFEM. The verification shows that the computational accuracy of SAFEM is high enough and its computational time is much shorter than ABAQUS. Moreover, experimental verification was carried out and the prediction derived from SAFEM is consistent with the measurement. Therefore, the SAFEM is feasible to reliably predict the dynamic response of asphalt pavement under moving loads, thus proving beneficial to road administration in assessing the pavement's state.

Whole-body computed tomography in trauma patients: optimization of the patient scanning position significantly shortens examination time while maintaining diagnostic image quality.

PubMed

Hickethier, Tilman; Mammadov, Kamal; Baeßler, Bettina; Lichtenstein, Thorsten; Hinkelbein, Jochen; Smith, Lucy; Plum, Patrick Sven; Chon, Seung-Hun; Maintz, David; Chang, De-Hua

2018-01-01

The study was conducted to compare examination time and artifact vulnerability of whole-body computed tomographies (wbCTs) for trauma patients using conventional or optimized patient positioning. Examination time was measured in 100 patients scanned with conventional protocol (Group A: arms positioned alongside the body for head and neck imaging and over the head for trunk imaging) and 100 patients scanned with optimized protocol (Group B: arms flexed on a chest pillow without repositioning). Additionally, influence of two different scanning protocols on image quality in the most relevant body regions was assessed by two blinded readers. Total wbCT duration was about 35% or 3:46 min shorter in B than in A. Artifacts in aorta (27 vs 6%), liver (40 vs 8%) and spleen (27 vs 5%) occurred significantly more often in B than in A. No incident of non-diagnostic image quality was reported, and no significant differences for lungs and spine were found. An optimized wbCT positioning protocol for trauma patients allows a significant reduction of examination time while still maintaining diagnostic image quality.

C. botulinum inactivation kinetics implemented in a computational model of a high-pressure sterilization process.

PubMed

Juliano, Pablo; Knoerzer, Kai; Fryer, Peter J; Versteeg, Cornelis

2009-01-01

High-pressure, high-temperature (HPHT) processing is effective for microbial spore inactivation using mild preheating, followed by rapid volumetric compression heating and cooling on pressure release, enabling much shorter processing times than conventional thermal processing for many food products. A computational thermal fluid dynamic (CTFD) model has been developed to model all processing steps, including the vertical pressure vessel, an internal polymeric carrier, and food packages in an axis-symmetric geometry. Heat transfer and fluid dynamic equations were coupled to four selected kinetic models for the inactivation of C. botulinum; the traditional first-order kinetic model, the Weibull model, an nth-order model, and a combined discrete log-linear nth-order model. The models were solved to compare the resulting microbial inactivation distributions. The initial temperature of the system was set to 90 degrees C and pressure was selected at 600 MPa, holding for 220 s, with a target temperature of 121 degrees C. A representation of the extent of microbial inactivation throughout all processing steps was obtained for each microbial model. Comparison of the models showed that the conventional thermal processing kinetics (not accounting for pressure) required shorter holding times to achieve a 12D reduction of C. botulinum spores than the other models. The temperature distribution inside the vessel resulted in a more uniform inactivation distribution when using a Weibull or an nth-order kinetics model than when using log-linear kinetics. The CTFD platform could illustrate the inactivation extent and uniformity provided by the microbial models. The platform is expected to be useful to evaluate models fitted into new C. botulinum inactivation data at varying conditions of pressure and temperature, as an aid for regulatory filing of the technology as well as in process and equipment design.

Expectations Among Academic Clinicians of Inpatient Imaging Turnaround Time: Does it Correlate with Satisfaction?

PubMed

Chan, Keith T; Carroll, Tamara; Linnau, Ken F; Lehnert, Bruce

2015-11-01

Imaging report turnaround time (RTAT) is an important measure of radiology performance and has become the leading priority in customer satisfaction surveys conducted among nonradiologists, who may not be familiar with the imaging workflow. Our aim was to assess physicians' expected RTAT for commonly ordered studies and determine if satisfaction correlates with met expectations. Retrospective review of inpatient imaging was conducted at a single academic institution, and RTAT for 18,414 studies was calculated. Examinations were grouped by study type, priority, and time of day. A cross-sectional survey instrument was completed by 48 internal medicine and surgery resident physicians with questions regarding RTAT and their level of satisfaction with various examinations. Actual RTAT ranged from 1.6 to 26.0 hours, with chest radiographs and computed tomographies generally faster than magnetic resonance images and ultrasounds. Urgent (STAT) examinations and those ordered during business hours have shorter RTAT. The time for image interpretation largely contributed to the RTAT because of the lack of night-time radiology coverage. Referring physician expectations were consistently shorter than actual RTAT, ranging from 30 minutes to 24 hours. Overall satisfaction scores were inversely correlated with RTAT, with a strong correlation to the time from study order to imaging (r(2) = 0.63) and a weak correlation to the image interpretation time (r(2) = 0.17). Satisfaction scores did not correlate with whether the actual RTAT met expectations (r(2) = 0.06). Referring physician satisfaction is likely multifactorial. Although RTAT has been reported as a priority, shortening turnaround time alone may not directly improve clinician satisfaction. Copyright © 2015 AUR. Published by Elsevier Inc. All rights reserved.

Electrical control of a solid-state flying qubit.

PubMed

Yamamoto, Michihisa; Takada, Shintaro; Bäuerle, Christopher; Watanabe, Kenta; Wieck, Andreas D; Tarucha, Seigo

2012-03-18

Solid-state approaches to quantum information technology are attractive because they are scalable. The coherent transport of quantum information over large distances is a requirement for any practical quantum computer and has been demonstrated by coupling super-conducting qubits to photons. Single electrons have also been transferred between distant quantum dots in times shorter than their spin coherence time. However, until now, there have been no demonstrations of scalable 'flying qubit' architectures-systems in which it is possible to perform quantum operations on qubits while they are being coherently transferred-in solid-state systems. These architectures allow for control over qubit separation and for non-local entanglement, which makes them more amenable to integration and scaling than static qubit approaches. Here, we report the transport and manipulation of qubits over distances of 6 µm within 40 ps, in an Aharonov-Bohm ring connected to two-channel wires that have a tunable tunnel coupling between channels. The flying qubit state is defined by the presence of a travelling electron in either channel of the wire, and can be controlled without a magnetic field. Our device has shorter quantum gates (<1 µm), longer coherence lengths (∼86 µm at 70 mK) and higher operating frequencies (∼100 GHz) than other solid-state implementations of flying qubits.

The effect of magnification loupes on the performance of preclinical dental students.

PubMed

Maggio, Margrit P; Villegas, Hilda; Blatz, Markus B

2011-01-01

optical magnifying devices such as magnification loupes are increasingly used in clinical practice and educational settings. However, scientific evidence to validate their benefits is limited. This study assessed the effect of dental magnification loupes on psychomotor skill acquisition during a preclinical operative dentistry course. the performance of first-year dental students was assessed during an Advanced Simulation Course (AS) using virtual reality-based technology (VRBT) training. The test group consisted of 116 dental students using magnification loupes (+MAG), while students not using them (-MAG, n = 116) served as the control. The following parameters were evaluated: number of successfully passing preparation procedures per course rotation, amount of time per tooth preparation, number of times students needed computer assistance and evaluation, and amount of time spent in the computer assistance and evaluation mode per procedure. Data were collected on each student through VRBT during the preparation procedure and stored on a closed network server computer. Unpaired t tests were used to analyze mean differences between the groups. In addition, student acceptance of magnification loupes was measured and evaluated through survey interpretation. +MAG students completed more preparations, worked faster per procedure, and used the computer-assisted evaluation less frequently and for shorter periods, therefore displaying greater overall performance. The survey revealed a high degree of student acceptance of using magnification. dental magnification loupes significantly enhanced student performance during preclinical dental education and were considered an effective adjunct by the students who used them.

RSA cryptography and multi prime RSA cryptography

NASA Astrophysics Data System (ADS)

Sani, Nur Atiqah Abdul; Kamarulhaili, Hailiza

2017-08-01

RSA cryptography is one of the most powerful and popular cryptosystem which is being applied until now. There is one variant of RSA cryptography named Multi Prime RSA (MPRSA) cryptography. MPRSA cryptography is the improved version of RSA cryptography. We only need to modify a few steps in key generation part and apply the Chinese Remainder Theorem (CRT) in the decryption part to get the MPRSA algorithm. The focus of this research is to compare between the standard RSA cryptography and MPRSA cryptography in a few aspects. The research shows that MPRSA cryptography is more efficient than the RSA cryptography. Time complexity using Mathematica software is also conducted and it is proven that MPRSA cryptography has shorter time taken. It also implies the computational time is less than RSA cryptography. Mathematica software version 9.0 and a laptop HP ProBook 4331s are used to check the timing and to implement both algorithms.

Nanosecond-timescale spin transfer using individual electrons in a quadruple-quantum-dot device

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

Baart, T. A.; Jovanovic, N.; Vandersypen, L. M. K.

2016-07-25

The ability to coherently transport electron-spin states between different sites of gate-defined semiconductor quantum dots is an essential ingredient for a quantum-dot-based quantum computer. Previous shuttles using electrostatic gating were too slow to move an electron within the spin dephasing time across an array. Here, we report a nanosecond-timescale spin transfer of individual electrons across a quadruple-quantum-dot device. Utilizing enhanced relaxation rates at a so-called hot spot, we can upper bound the shuttle time to at most 150 ns. While actual shuttle times are likely shorter, 150 ns is already fast enough to preserve spin coherence in, e.g., silicon based quantum dots.more » This work therefore realizes an important prerequisite for coherent spin transfer in quantum dot arrays.« less

Duration of untreated illness as a predictor of treatment response and clinical course in generalized anxiety disorder.

PubMed

Altamura, A C; Dell'osso, Bernardo; D'Urso, Nazario; Russo, Michela; Fumagalli, Sara; Mundo, Emanuela

2008-05-01

The aim of the present study was to investigate the impact of the duration of untreated illness (DUI)-defined as the time elapsing between the onset of generalized anxiety disorder (GAD) and the first adequate pharmacologic treatment-on treatment response and clinical course in a sample of subjects with GAD. One hundred patients with GAD, diagnosed according to Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition-Text Revision criteria, were enrolled and their main demographic and clinical features collected. Patients were then treated with selective serotonin reuptake inhibitors or venlafaxine for 8 weeks in open-label conditions. Treatment response and other clinical variables were analyzed after dividing the sample into two groups according to DUI (DUI 12 months). When the DUI was computed with respect to the first antidepressant treatment (DUI-AD), a higher improvement (Clinical Global Impressions-Severity of Illness scale) after the pharmacologic treatment was found in the group with a shorter DUI (analysis of variance with repeated measures: time effect F=654.975, P<.001; group effect: F=4.369, P=.039). When computed with respect to the first treatment with benzodiazepines (DUI-BDZ), the two groups did not show any significant difference in treatment response (time effect: F=652.183, P<.001; group effect: F=0.009, P=.924). In addition, patients with a longer DUI (DUI-BDZ or DUI-AD) showed an earlier age at onset, a longer duration of illness and a higher rate of comorbid psychiatric disorders with onset later than GAD. Results from this preliminary study seem to suggest that a shorter DUI-AD may determine a better response to pharmacologic treatment in patients with GAD, and that a longer DUI (DUI-BDZ and DUI-AD) may be associated to a worse clinical course. Further investigation on the relationship between DUI and GAD is needed.

The spatial return level of aggregated hourly extreme rainfall in Peninsular Malaysia

NASA Astrophysics Data System (ADS)

Shaffie, Mardhiyyah; Eli, Annazirin; Wan Zin, Wan Zawiah; Jemain, Abdul Aziz

2015-07-01

This paper is intended to ascertain the spatial pattern of extreme rainfall distribution in Peninsular Malaysia at several short time intervals, i.e., on hourly basis. Motivation of this research is due to historical records of extreme rainfall in Peninsular Malaysia, whereby many hydrological disasters at this region occur within a short time period. The hourly periods considered are 1, 2, 3, 6, 12, and 24 h. Many previous hydrological studies dealt with daily rainfall data; thus, this study enables comparison to be made on the estimated performances between daily and hourly rainfall data analyses so as to identify the impact of extreme rainfall at a shorter time scale. Return levels based on the time aggregate considered are also computed. Parameter estimation using L-moment method for four probability distributions, namely, the generalized extreme value (GEV), generalized logistic (GLO), generalized Pareto (GPA), and Pearson type III (PE3) distributions were conducted. Aided with the L-moment diagram test and mean square error (MSE) test, GLO was found to be the most appropriate distribution to represent the extreme rainfall data. At most time intervals (10, 50, and 100 years), the spatial patterns revealed that the rainfall distribution across the peninsula differ for 1- and 24-h extreme rainfalls. The outcomes of this study would provide additional information regarding patterns of extreme rainfall in Malaysia which may not be detected when considering only a higher time scale such as daily; thus, appropriate measures for shorter time scales of extreme rainfall can be planned. The implementation of such measures would be beneficial to the authorities to reduce the impact of any disastrous natural event.

Waiting times for hospital admissions: the impact of GP fundholding.

PubMed

Propper, Carol; Croxson, Bronwyn; Shearer, Arran

2002-03-01

Waiting times for hospital care are a significant issue in the UK National Health Service (NHS). The reforms of the health service in 1990 gave a subset of family doctors (GP fundholders) both the ability to choose the hospital where their patients were treated and the means to pay for some services. One of the key factors influencing family doctors' choice of hospital was patient waiting time. However, without cash inducements, hospitals would get no direct reward from giving shorter waiting times to a subset of patients. Using a unique dataset, we investigate whether GP fundholders were able to secure shorter waiting times for their patients, whether they were able to do so in cases where they had no financial rewards to offer hospitals, and whether the impact of fundholding spilled over into shorter waiting times for all patients.

Closed-loop controller for chest compressions based on coronary perfusion pressure: a computer simulation study.

PubMed

Wang, Chunfei; Zhang, Guang; Wu, Taihu; Zhan, Ningbo; Wang, Yaling

2016-03-01

High-quality cardiopulmonary resuscitation contributes to cardiac arrest survival. The traditional chest compression (CC) standard, which neglects individual differences, uses unified standards for compression depth and compression rate in practice. In this study, an effective and personalized CC method for automatic mechanical compression devices is provided. We rebuild Charles F. Babbs' human circulation model with a coronary perfusion pressure (CPP) simulation module and propose a closed-loop controller based on a fuzzy control algorithm for CCs, which adjusts the CC depth according to the CPP. Compared with a traditional proportion-integration-differentiation (PID) controller, the performance of the fuzzy controller is evaluated in computer simulation studies. The simulation results demonstrate that the fuzzy closed-loop controller results in shorter regulation time, fewer oscillations and smaller overshoot than traditional PID controllers and outperforms the traditional PID controller for CPP regulation and maintenance.

7 CFR 58.101 - Meaning of words.

Code of Federal Regulations, 2012 CFR

2012-01-01

... solution for the destruction of most human pathogens and other vegetative microorganisms to a level... the milk product, or the health of consumers. Sanitizing solutions shall comply with 21 CFR 178.1010... (higher heat shorter time pasteurization) 1.0 second. 194 °F (higher heat shorter time pasteurization) 0.5...

7 CFR 58.101 - Meaning of words.

Code of Federal Regulations, 2013 CFR

2013-01-01

... solution for the destruction of most human pathogens and other vegetative microorganisms to a level... the milk product, or the health of consumers. Sanitizing solutions shall comply with 21 CFR 178.1010... (higher heat shorter time pasteurization) 1.0 second. 194 °F (higher heat shorter time pasteurization) 0.5...

7 CFR 58.101 - Meaning of words.

Code of Federal Regulations, 2014 CFR

2014-01-01

... solution for the destruction of most human pathogens and other vegetative microorganisms to a level... the milk product, or the health of consumers. Sanitizing solutions shall comply with 21 CFR 178.1010... (higher heat shorter time pasteurization) 1.0 second. 194 °F (higher heat shorter time pasteurization) 0.5...

Improved nearest codeword search scheme using a tighter kick-out condition

NASA Astrophysics Data System (ADS)

Hwang, Kuo-Feng; Chang, Chin-Chen

2001-09-01

Using a tighter kick-out condition as a faster approach to nearest codeword searches is proposed. The proposed scheme finds the nearest codeword that is identical to the one found using a full search. However, using our scheme, the search time is much shorter. Our scheme first establishes a tighter kick-out condition. Then, the temporal nearest codeword can be obtained from the codewords that survive the tighter condition. Finally, the temporal nearest codeword cooperatives with the query vector to constitute a better kick-out condition. In other words, more codewords can be excluded without actually computing the distances between the bypassed codewords and the query vector. Comparison to previous work are included to present the benefits of the proposed scheme in relation to search time.

Dose-time relationships for post-irradiation cutaneous telangiectasia

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

Cohen, L.; Ubaldi, S.E.

1977-01-01

Seventy-five patients who had received electron beam radiation a year or more previously were studied. The irradiated skin portals were photographed and late reactions graded in terms of the number and severity of telangiectatic lesions observed. The skin dose, number of fractions, overall treatment time and irradiated volume were recorded in each case. A Strandqvist-type iso-effect line was derived for this response. A multi-probit search program also was used to derive best-fitting cell population kinetic parameters for the same data. From these parameters a comprehensive iso-effect table could be computed for a wide range of treatment schedules including daily treatmentmore » as well as fractionation at shorter and longer intervals; this provided a useful set of normal tissue tolerance limits for late effects.« less

[Eye movement study in multiple object search process].

PubMed

Xu, Zhaofang; Liu, Zhongqi; Wang, Xingwei; Zhang, Xin

2017-04-01

The aim of this study is to investigate the search time regulation of objectives and eye movement behavior characteristics in the multi-objective visual search. The experimental task was accomplished with computer programming and presented characters on a 24 inch computer display. The subjects were asked to search three targets among the characters. Three target characters in the same group were of high similarity degree while those in different groups of target characters and distraction characters were in different similarity degrees. We recorded the search time and eye movement data through the whole experiment. It could be seen from the eye movement data that the quantity of fixation points was large when the target characters and distraction characters were similar. There were three kinds of visual search patterns for the subjects including parallel search, serial search, and parallel-serial search. In addition, the last pattern had the best search performance among the three search patterns, that is, the subjects who used parallel-serial search pattern spent shorter time finding the target. The order that the targets presented were able to affect the search performance significantly; and the similarity degree between target characters and distraction characters could also affect the search performance.

Three-dimensional printing enhances preparation for repair of double outlet right ventricular surgery.

PubMed

Zhao, Liyun; Zhou, Sijie; Fan, Taibing; Li, Bin; Liang, Weijie; Dong, Haoju

2018-01-01

To assess the clinical value of three-dimensional (3D) printing technology for treatment strategies for complex double outlet right ventricle (DORV). Twenty-five patients with complex double outlet right ventricle were enrolled in this study. The patients were divided into two groups: 3D printing group (eight patients) and a non-3-D printing control group (17 patients). The cardiac images of patients in the 3D printing group were transformed to Digital Imaging and Communications and were segmented and reconstructed to create a heart model. No cardiac models were created in the control group. A Pearson coefficient analysis was used to assess the correlation between measurements of 3D printed models and computed tomography angiography (CTA) data. Pre-operative assessment and planning were performed with 3D printed models, and then operative time and recovery time were compared between the two groups. There was good correlation (r = 0.977) between 3D printed models and CTA data. Patients in the 3D printing group had shorter aortic cross-clamp time (102.88 vs 127.76 min, P = 0.094) and cardiopulmonary bypass time (151.63 vs 184.24 min; P = 0.152) than patients in the control group. Patients with 3D printed models had significantly lower mechanical ventilation time (56.43 vs 96.76 h, P = 0.040) and significantly shorter intensive care unit time (99.04 vs 166.94 h, P = 0.008) than patients in the control group. 3D printed models can accurately demonstrate anatomic structures and are useful for pre-operative treatment strategies in DORV. © 2018 Wiley Periodicals, Inc.

Conventional versus traction-assisted endoscopic submucosal dissection for gastric neoplasms: a multicenter, randomized controlled trial (with video).

PubMed

Yoshida, Masao; Takizawa, Kohei; Suzuki, Sho; Koike, Yoshiki; Nonaka, Satoru; Yamasaki, Yasushi; Minagawa, Takeyoshi; Sato, Chiko; Takeuchi, Chihiro; Watanabe, Ko; Kanzaki, Hiromitsu; Morimoto, Hiroyuki; Yano, Takafumi; Sudo, Kosuke; Mori, Keita; Gotoda, Takuji; Ono, Hiroyuki

2018-05-01

The aim of this study was to clarify whether dental floss clip (DFC) traction improves the technical outcomes of endoscopic submucosal dissection (ESD). A superiority, randomized control trial was conducted at 14 institutions across Japan. Patients with single gastric neoplasm meeting the indications of the Japanese guidelines for gastric treatment were enrolled and assigned to receive conventional ESD or DFC traction-assisted ESD (DFC-ESD). Randomization was performed according to a computer-generated random sequence with stratification by institution, tumor location, tumor size, and operator experience. The primary endpoint was ESD procedure time, defined as the time from the start of the submucosal injection to the end of the tumor removal procedure. Between July 2015 and September 2016, 640 patients underwent randomization. Of these, 316 patients who underwent conventional ESD and 319 patients who underwent DFC-ESD were included in our analysis. The mean ESD procedure time was 60.7 and 58.1 minutes for conventional ESD and DFC-ESD, respectively (P = .45). Perforation was less frequent in the DFC-ESD group (2.2% vs .3%, P = .04). For lesions located in the greater curvature of the upper or middle stomach, the mean procedure time was significantly shorter in the DFC-ESD group (104.1 vs 57.2 minutes, P = .01). Our findings suggest that DFC-ESD does not result in shorter procedure time in the overall patient population, but it can reduce the risk of perforation. When selectively applied to lesions located in the greater curvature of the upper or middle stomach, DFC-ESD provides a remarkable reduction in procedure time. Copyright © 2018 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.

Modeling cell adhesion and proliferation: a cellular-automata based approach.

PubMed

Vivas, J; Garzón-Alvarado, D; Cerrolaza, M

Cell adhesion is a process that involves the interaction between the cell membrane and another surface, either a cell or a substrate. Unlike experimental tests, computer models can simulate processes and study the result of experiments in a shorter time and lower costs. One of the tools used to simulate biological processes is the cellular automata, which is a dynamic system that is discrete both in space and time. This work describes a computer model based on cellular automata for the adhesion process and cell proliferation to predict the behavior of a cell population in suspension and adhered to a substrate. The values of the simulated system were obtained through experimental tests on fibroblast monolayer cultures. The results allow us to estimate the cells settling time in culture as well as the adhesion and proliferation time. The change in the cells morphology as the adhesion over the contact surface progress was also observed. The formation of the initial link between cell and the substrate of the adhesion was observed after 100 min where the cell on the substrate retains its spherical morphology during the simulation. The cellular automata model developed is, however, a simplified representation of the steps in the adhesion process and the subsequent proliferation. A combined framework of experimental and computational simulation based on cellular automata was proposed to represent the fibroblast adhesion on substrates and changes in a macro-scale observed in the cell during the adhesion process. The approach showed to be simple and efficient.

Microdosimetric study for nanosecond pulsed electric fields on a cell circuit model with nucleus.

PubMed

Denzi, Agnese; Merla, Caterina; Camilleri, Paola; Paffi, Alessandra; d'Inzeo, Guglielmo; Apollonio, Francesca; Liberti, Micaela

2013-10-01

Recently, scientific interest in electric pulses, always more intense and shorter and able to induce biological effects on both plasma and nuclear membranes, has greatly increased. Hence, microdosimetric models that include internal organelles like the nucleus have assumed increasing importance. In this work, a circuit model of the cell including the nucleus is proposed, which accounts for the dielectric dispersion of all cell compartments. The setup of the dielectric model of the nucleus is of fundamental importance in determining the transmembrane potential (TMP) induced on the nuclear membrane; here, this is demonstrated by comparing results for three different sets of nuclear dielectric properties present in the literature. The results have been compared, even including or disregarding the dielectric dispersion of the nucleus. The main differences have been found when using pulses shorter than 10 ns. This is due to the fact that the high spectral components of the shortest pulses are differently taken into account by the nuclear membrane transfer functions computed with and without nuclear dielectric dispersion. The shortest pulses are also the most effective in porating the intracellular structures, as confirmed by the time courses of the TMP calculated across the plasma and nuclear membranes. We show how dispersive nucleus models are unavoidable when dealing with pulses shorter than 10 ns because of the large spectral contents arriving above 100 MHz, i.e., over the typical relaxation frequencies of the dipolar mechanism of the molecules constituting the nuclear membrane and the subcellular cell compartments.

The Block V Receiver fast acquisition algorithm for the Galileo S-band mission

NASA Technical Reports Server (NTRS)

Aung, M.; Hurd, W. J.; Buu, C. M.; Berner, J. B.; Stephens, S. A.; Gevargiz, J. M.

1994-01-01

A fast acquisition algorithm for the Galileo suppressed carrier, subcarrier, and data symbol signals under low data rate, signal-to-noise ratio (SNR) and high carrier phase-noise conditions has been developed. The algorithm employs a two-arm fast Fourier transform (FFT) method utilizing both the in-phase and quadrature-phase channels of the carrier. The use of both channels results in an improved SNR in the FFT acquisition, enabling the use of a shorter FFT period over which the carrier instability is expected to be less significant. The use of a two-arm FFT also enables subcarrier and symbol acquisition before carrier acquisition. With the subcarrier and symbol loops locked first, the carrier can be acquired from an even shorter FFT period. Two-arm tracking loops are employed to lock the subcarrier and symbol loops parameter modification to achieve the final (high) loop SNR in the shortest time possible. The fast acquisition algorithm is implemented in the Block V Receiver (BVR). This article describes the complete algorithm design, the extensive computer simulation work done for verification of the design and the analysis, implementation issues in the BVR, and the acquisition times of the algorithm. In the expected case of the Galileo spacecraft at Jupiter orbit insertion PD/No equals 14.6 dB-Hz, R(sym) equals 16 symbols per sec, and the predicted acquisition time of the algorithm (to attain a 0.2-dB degradation from each loop to the output symbol SNR) is 38 sec.

Retrograde light-guided laryngoscopy for tracheal intubation: clinical practice and comparison with conventional direct laryngoscopy.

PubMed

Yang, Tao; Hou, Jiong; Li, Jinbao; Zhang, Xu; Zhu, Xiaoyan; Ni, Wen; Mao, Yanfei; Deng, Xiaoming

2013-05-01

Tracheal intubation with conventional laryngoscopy requires many trials until beginners are sufficiently skilled in intubating patients safely. To facilitate intubation, the authors used retrograde light-guided laryngoscopy (RLGL) and compared its feasibility with conventional direct laryngoscopy (DL). Twenty operators participated in a prospective, randomized, open-label, parallel-arm study. These operators intubated 205 patients randomly according to a computer-generated procedure by using either DL or RLGL (five intubations with each technique). The primary outcome was the success rate of tracheal intubation. The authors evaluated the success rate of tracheal intubation, the time to glottic exposure and tracheal intubation, and the Cormack and Lehane grades. Compared with DL, the success rate was greater in the RLGL group for all five intubations (72% vs. 47%; rate difference, 25%; 95% CI [11.84-38.16%], P < 0.001). This was associated with a shorter time to glottic exposure (median [25th and 75th percentile]; 27 [15; 42] vs. 45 [30; 73] s, P < 0.001), shorter intubation time (66 [44; 120] vs. 120 [69; 120] s, P < 0.001), and decreased throat soreness (mean ± SD; visual analog scale, 2.1 ± 0.9 vs. 3.7 ± 1.0 cm, P = 0.001) in the RLGL group compared to the DL group. RLGL is an alternative intubation technique. In our study, it enables beginners to intubate patients more successfully and quickly than conventional DL.

Real-time mobile phone dialing system based on SSVEP

NASA Astrophysics Data System (ADS)

Wang, Dongsheng; Kobayashi, Toshiki; Cui, Gaochao; Watabe, Daishi; Cao, Jianting

2017-03-01

Brain computer interface (BCI) systems based on the steady state visual evoked potential (SSVEP) provide higher information transfer rates and require shorter training time than BCI systems using other brain signals. It has been widely used in brain science, rehabilitation engineering, biomedical engineering and intelligent information processing. In this paper, we present a real-time mobile phone dialing system based on SSVEP, and it is more portable than other dialing system because the flashing dial interface is set on a small tablet. With this online BCI system, we can take advantage of this system based on SSVEP to identify the specific frequency on behalf of a number using canonical correlation analysis (CCA) method and dialed out successfully without using any physical movements such as finger tapping. This phone dialing system will be promising to help disable patients to improve the quality of lives.

[Comparison of the results of laparotomy and laparoscopic surgery in patients with Crohn's disease].

PubMed

Horváth, Gyula; Simonka, Zsolt; Lázár, György

2014-01-05

Crohn's disease is an inflammatory bowel disease which may affect different parts of the gastrointestinal tract. To compare retrospectively the results of laparotomy and laparoscopic surgery performed in patients with Crohn's disease between January 1, 2005 and October 31, 2012 in the Department of Surgery, University of Szeged, Hungary. Patients were divided into two groups based on the types of surgery; 103 patients underwent laparotomy and 30 patients had laparoscopic surgery programmed. 22 patients had 24 primary acute interventions. The mean age was significantly lower in the laparoscopic surgery group (p = 0.042). The laparoscopic ileocecal resections have been found significantly shorter than laparotomies (p = 0.033). When ileocecal resection was performed the operation time was significantly longer (p = 0.033) while hospitalization time (p = 0.025) and intensive care unit treatment time (p<0.001) were shorter and the bowel passage also started earlier in the laparoscopic group as compared to the laparotomy group. Laparoscopic surgery results in smaller surgical trauma, better cosmetic outcome, shorter hospitalization time and not higher complication- and morbidity-rate as well as shorter operation time in certain cases. However, it requires more qualified surgical team and the operation expenses are higher.

Installing and implementing a computer-based patient record system in sub-Saharan Africa: the Mosoriot Medical Record System.

PubMed

Rotich, Joseph K; Hannan, Terry J; Smith, Faye E; Bii, John; Odero, Wilson W; Vu, Nguyen; Mamlin, Burke W; Mamlin, Joseph J; Einterz, Robert M; Tierney, William M

2003-01-01

The authors implemented an electronic medical record system in a rural Kenyan health center. Visit data are recorded on a paper encounter form, eliminating duplicate documentation in multiple clinic logbooks. Data are entered into an MS-Access database supported by redundant power systems. The system was initiated in February 2001, and 10,000 visit records were entered for 6,190 patients in six months. The authors present a summary of the clinics visited, diagnoses made, drugs prescribed, and tests performed. After system implementation, patient visits were 22% shorter. They spent 58% less time with providers (p < 0.001) and 38% less time waiting (p = 0.06). Clinic personnel spent 50% less time interacting with patients, two thirds less time interacting with each other, and more time in personal activities. This simple electronic medical record system has bridged the "digital divide." Financial and technical sustainability by Kenyans will be key to its future use and development.

Concept of Operations Evaluation for Using Remote-Guidance Ultrasound for Exploration Spaceflight.

PubMed

Hurst, Victor W; Peterson, Sean; Garcia, Kathleen; Ebert, Douglas; Ham, David; Amponsah, David; Dulchavsky, Scott

2015-12-01

Remote-guidance (RG) techniques aboard the International Space Station (ISS) have enabled astronauts to collect diagnostic-level ultrasound (US) images. Exploration-class missions will likely require nonformally trained sonographers to operate with greater autonomy given longer communication delays (> 6 s for missions beyond the Moon) and blackouts. Training requirements for autonomous collection of US images by non-US experts are being determined. Novice US operators were randomly assigned to one of three groups to collect standardized US images while drawing expertise from A) RG only, B) a computer training tool only, or C) both RG and a computer training tool. Images were assessed for quality and examination duration. All operators were given a 10-min standardized generic training session in US scanning. The imaging task included: 1) bone fracture assessment in a phantom and 2) Focused Assessment with Sonography in Trauma (FAST) examination in a healthy volunteer. A human factors questionnaire was also completed. Mean time for group B during FAST was shorter (20.4 vs. 22.7 min) than time for the other groups. Image quality scoring was lower than in groups A or C, but all groups produced images of acceptable diagnostic quality. RG produces US images of higher quality than those produced with only computer-based instruction. Extended communication delays in exploration missions will eliminate the option of real-time guidance, thus requiring autonomous operation. The computer program used appears effective and could be a model for future digital US expertise banks. Terrestrially, it also provides adequate self-training and mentoring mechanisms.

Microdot - A Four-Bit Microcontroller Designed for Distributed Low-End Computing in Satellites

NASA Astrophysics Data System (ADS)

2002-03-01

Many satellites are an integrated collection of sensors and actuators that require dedicated real-time control. For single processor systems, additional sensors require an increase in computing power and speed to provide the multi-tasking capability needed to service each sensor. Faster processors cost more and consume more power, which taxes a satellite's power resources and may lead to shorter satellite lifetimes. An alternative design approach is a distributed network of small and low power microcontrollers designed for space that handle the computing requirements of each individual sensor and actuator. The design of microdot, a four-bit microcontroller for distributed low-end computing, is presented. The design is based on previous research completed at the Space Electronics Branch, Air Force Research Laboratory (AFRL/VSSE) at Kirtland AFB, NM, and the Air Force Institute of Technology at Wright-Patterson AFB, OH. The Microdot has 29 instructions and a 1K x 4 instruction memory. The distributed computing architecture is based on the Philips Semiconductor I2C Serial Bus Protocol. A prototype was implemented and tested using an Altera Field Programmable Gate Array (FPGA). The prototype was operable to 9.1 MHz. The design was targeted for fabrication in a radiation-hardened-by-design gate-array cell library for the TSMC 0.35 micrometer CMOS process.

Application of Dynamic Analysis in Semi-Analytical Finite Element Method

PubMed Central

Oeser, Markus

2017-01-01

Analyses of dynamic responses are significantly important for the design, maintenance and rehabilitation of asphalt pavement. In order to evaluate the dynamic responses of asphalt pavement under moving loads, a specific computational program, SAFEM, was developed based on a semi-analytical finite element method. This method is three-dimensional and only requires a two-dimensional FE discretization by incorporating Fourier series in the third dimension. In this paper, the algorithm to apply the dynamic analysis to SAFEM was introduced in detail. Asphalt pavement models under moving loads were built in the SAFEM and commercial finite element software ABAQUS to verify the accuracy and efficiency of the SAFEM. The verification shows that the computational accuracy of SAFEM is high enough and its computational time is much shorter than ABAQUS. Moreover, experimental verification was carried out and the prediction derived from SAFEM is consistent with the measurement. Therefore, the SAFEM is feasible to reliably predict the dynamic response of asphalt pavement under moving loads, thus proving beneficial to road administration in assessing the pavement’s state. PMID:28867813

Minimally invasive mitral valve surgery through right mini-thoracotomy: recommendations for good exposure, stable cardiopulmonary bypass, and secure myocardial protection.

PubMed

Ito, Toshiaki

2015-07-01

An apparent advantage of minimally invasive mitral surgery through right mini-thoracotomy is cosmetic appearance. Possible advantages of this procedure are a shorter ventilation time, shorter hospital stay, and less blood transfusion. With regard to hard endpoints, such as operative mortality, freedom from reoperation, or cardiac death, this method is reportedly equivalent, but not superior, to the standard median sternotomy technique. However, perfusion-related complications (e.g., stroke, vascular damage, and limb ischemia) tend to occur more frequently in minimally invasive technique than with the standard technique. In addition, valve repair through a small thoracotomy is technically demanding. Therefore, screening out patients who are not appropriate for performing minimally invasive surgery is the first step. Vascular disease and inadequate anatomy can be evaluated with contrast-enhanced computed tomography. Peripheral cannulation should be carefully performed, using transesophageal echocardiography guidance. Preoperative detailed planning of the valve repair process is desirable because every step is time-consuming in minimally invasive surgery. Three-dimensional echocardiography is a powerful tool for this purpose. For satisfactory exposure and detailed observation of the valve, a special left atrial retractor and high-definition endoscope are useful. Valve repair can be performed in minimally invasive surgery as long as cardiopulmonary bypass is stable and bloodless exposure of the valve is obtained.

Reduction in patient burdens with graphical computerized adaptive testing on the ADL scale: tool development and simulation.

PubMed

Chien, Tsair-Wei; Wu, Hing-Man; Wang, Weng-Chung; Castillo, Roberto Vasquez; Chou, Willy

2009-05-05

The aim of this study was to verify the effectiveness and efficacy of saving time and reducing burden for patients, nurses, and even occupational therapists through computer adaptive testing (CAT). Based on an item bank of the Barthel Index (BI) and the Frenchay Activities Index (FAI) for assessing comprehensive activities of daily living (ADL) function in stroke patients, we developed a visual basic application (VBA)-Excel CAT module, and (1) investigated whether the averaged test length via CAT is shorter than that of the traditional all-item-answered non-adaptive testing (NAT) approach through simulation, (2) illustrated the CAT multimedia on a tablet PC showing data collection and response errors of ADL clinical functional measures in stroke patients, and (3) demonstrated the quality control of endorsing scale with fit statistics to detect responding errors, which will be further immediately reconfirmed by technicians once patient ends the CAT assessment. The results show that endorsed items could be shorter on CAT (M = 13.42) than on NAT (M = 23) at 41.64% efficiency in test length. However, averaged ability estimations reveal insignificant differences between CAT and NAT. This study found that mobile nursing services, placed at the bedsides of patients could, through the programmed VBA-Excel CAT module, reduce the burden to patients and save time, more so than the traditional NAT paper-and-pencil testing appraisals.

Conventional plate fixation method versus pre-operative virtual simulation and three-dimensional printing-assisted contoured plate fixation method in the treatment of anterior pelvic ring fracture.

PubMed

Hung, Chun-Chi; Li, Yuan-Ta; Chou, Yu-Ching; Chen, Jia-En; Wu, Chia-Chun; Shen, Hsain-Chung; Yeh, Tsu-Te

2018-05-03

Treating pelvic fractures remains a challenging task for orthopaedic surgeons. We aimed to evaluate the feasibility, accuracy, and effectiveness of three-dimensional (3D) printing technology and computer-assisted virtual surgery for pre-operative planning in anterior ring fractures of the pelvis. We hypothesized that using 3D printing models would reduce operation time and significantly improve the surgical outcomes of pelvic fracture repair. We retrospectively reviewed the records of 30 patients with pelvic fractures treated by anterior pelvic fixation with locking plates (14 patients, conventional locking plate fixation; 16 patients, pre-operative virtual simulation with 3D, printing-assisted, pre-contoured, locking plate fixation). We compared operative time, instrumentation time, blood loss, and post-surgical residual displacements, as evaluated on X-ray films, among groups. Statistical analyses evaluated significant differences between the groups for each of these variables. The patients treated with the virtual simulation and 3D printing-assisted technique had significantly shorter internal fixation times, shorter surgery duration, and less blood loss (- 57 minutes, - 70 minutes, and - 274 ml, respectively; P < 0.05) than patients in the conventional surgery group. However, the post-operative radiological result was similar between groups (P > 0.05). The complication rate was less in the 3D printing group (1/16 patients) than in the conventional surgery group (3/14 patients). The 3D simulation and printing technique is an effective and reliable method for treating anterior pelvic ring fractures. With precise pre-operative planning and accurate execution of the procedures, this time-saving approach can provide a more personalized treatment plan, allowing for a safer orthopaedic surgery.

Molecular dynamics analysis of transitions between rotational isomers in polymethylene

NASA Astrophysics Data System (ADS)

Zúñiga, Ignacio; Bahar, Ivet; Dodge, Robert; Mattice, Wayne L.

1991-10-01

Molecular dynamics trajectories have been computed and analyzed for linear chains, with sizes ranging from C10H22 to C100H202, and for cyclic C100H200. All hydrogen atoms are included discretely. All bond lengths, bond angles, and torsion angles are variable. Hazard plots show a tendency, at very short times, for correlations between rotational isomeric transitions at bond i and i±2, in much the same manner as in the Brownian dynamics simulations reported by Helfand and co-workers. This correlation of next nearest neighbor bonds in isolated polyethylene chains is much weaker than the correlation found for next nearest neighbor CH-CH2 bonds in poly(1,4-trans-butadiene) confined to the channel formed by crystalline perhydrotriphenylene [Dodge and Mattice, Macromolecules 24, 2709 (1991)]. Less than half of the rotational isomeric transitions observed in the entire trajectory for C50H102 can be described as strongly coupled next nearest neighbor transitions. If correlated motions are identified with successive transitions, which occur within a time interval of Δt≤1 ps, only 18% of the transitions occur through cooperative motion of bonds i and i±2. An analysis of the entire data set of 2482 rotational isomeric state transitions, observed in a 3.7 ns trajectory for C50H102 at 400 K, was performed using a formalism that treats the transitions at different bonds as being independent. On time scales of 0.1 ns or longer, the analysis based on independent bonds accounts reasonably well for the results from the molecular dynamics simulations. At shorter times the molecular dynamics simulation reveals a higher mobility than implied by the analysis assuming independent bonds, presumably due to the influence of correlations that are important at shorter times.

77 FR 7640 - Self-Regulatory Organizations; BATS Y-Exchange, Inc.; Notice of Filing and Immediate...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-02-13

... 30 days after the date of the filing, or such shorter time as the Commission may designate, it has...-4(f)(6)(iii) \\8\\ permits the Commission to designate a shorter time if such action is consistent... without further delay. The Exchange notes that the introduction of the additional optional variation of...

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Federal Register 2010, 2011, 2012, 2013, 2014

2012-02-13

... 30 days after the date of the filing, or such shorter time as the Commission may designate, it has...-4(f)(6)(iii) \\8\\ permits the Commission to designate a shorter time if such action is consistent... trading costs without further delay. The Exchange notes that the introduction of the additional optional...

Dynamic gas temperature measurements using a personal computer for data acquisition and reduction

NASA Technical Reports Server (NTRS)

Fralick, Gustave C.; Oberle, Lawrence G.; Greer, Lawrence C., III

1993-01-01

This report describes a dynamic gas temperature measurement system. It has frequency response to 1000 Hz, and can be used to measure temperatures in hot, high pressure, high velocity flows. A personal computer is used for collecting and processing data, which results in a much shorter wait for results than previously. The data collection process and the user interface are described in detail. The changes made in transporting the software from a mainframe to a personal computer are described in appendices, as is the overall theory of operation.

An energy management for series hybrid electric vehicle using improved dynamic programming

NASA Astrophysics Data System (ADS)

Peng, Hao; Yang, Yaoquan; Liu, Chunyu

2018-02-01

With the increasing numbers of hybrid electric vehicle (HEV), management for two energy sources, engine and battery, is more and more important to achieve the minimum fuel consumption. This paper introduces several working modes of series hybrid electric vehicle (SHEV) firstly and then describes the mathematical model of main relative components in SHEV. On the foundation of this model, dynamic programming is applied to distribute energy of engine and battery on the platform of matlab and acquires less fuel consumption compared with traditional control strategy. Besides, control rule recovering energy in brake profiles is added into dynamic programming, so shorter computing time is realized by improved dynamic programming and optimization on algorithm.

Conjunctival impression cytology in computer users.

PubMed

Kumar, S; Bansal, R; Khare, A; Malik, K P S; Malik, V K; Jain, K; Jain, C

2013-01-01

It is known that the computer users develop the features of dry eye. To study the cytological changes in the conjunctiva using conjunctival impression cytology in computer users and a control group. Fifteen eyes of computer users who had used computers for more than one year and ten eyes of an age-and-sex matched control group (those who had not used computers) were studied by conjunctival impression cytology. Conjunctival impression cytology (CIC) results in the control group were of stage 0 and stage I while the computer user group showed CIC results between stages II to stage IV. Among the computer users, the majority ( > 90 %) showed stage III and stage IV changes. We found that those who used computers daily for long hours developed more CIC changes than those who worked at the computer for a shorter daily duration. © NEPjOPH.

Heterogeneous computing architecture for fast detection of SNP-SNP interactions.

PubMed

Sluga, Davor; Curk, Tomaz; Zupan, Blaz; Lotric, Uros

2014-06-25

The extent of data in a typical genome-wide association study (GWAS) poses considerable computational challenges to software tools for gene-gene interaction discovery. Exhaustive evaluation of all interactions among hundreds of thousands to millions of single nucleotide polymorphisms (SNPs) may require weeks or even months of computation. Massively parallel hardware within a modern Graphic Processing Unit (GPU) and Many Integrated Core (MIC) coprocessors can shorten the run time considerably. While the utility of GPU-based implementations in bioinformatics has been well studied, MIC architecture has been introduced only recently and may provide a number of comparative advantages that have yet to be explored and tested. We have developed a heterogeneous, GPU and Intel MIC-accelerated software module for SNP-SNP interaction discovery to replace the previously single-threaded computational core in the interactive web-based data exploration program SNPsyn. We report on differences between these two modern massively parallel architectures and their software environments. Their utility resulted in an order of magnitude shorter execution times when compared to the single-threaded CPU implementation. GPU implementation on a single Nvidia Tesla K20 runs twice as fast as that for the MIC architecture-based Xeon Phi P5110 coprocessor, but also requires considerably more programming effort. General purpose GPUs are a mature platform with large amounts of computing power capable of tackling inherently parallel problems, but can prove demanding for the programmer. On the other hand the new MIC architecture, albeit lacking in performance reduces the programming effort and makes it up with a more general architecture suitable for a wider range of problems.

Heterogeneous computing architecture for fast detection of SNP-SNP interactions

PubMed Central

2014-01-01

Background The extent of data in a typical genome-wide association study (GWAS) poses considerable computational challenges to software tools for gene-gene interaction discovery. Exhaustive evaluation of all interactions among hundreds of thousands to millions of single nucleotide polymorphisms (SNPs) may require weeks or even months of computation. Massively parallel hardware within a modern Graphic Processing Unit (GPU) and Many Integrated Core (MIC) coprocessors can shorten the run time considerably. While the utility of GPU-based implementations in bioinformatics has been well studied, MIC architecture has been introduced only recently and may provide a number of comparative advantages that have yet to be explored and tested. Results We have developed a heterogeneous, GPU and Intel MIC-accelerated software module for SNP-SNP interaction discovery to replace the previously single-threaded computational core in the interactive web-based data exploration program SNPsyn. We report on differences between these two modern massively parallel architectures and their software environments. Their utility resulted in an order of magnitude shorter execution times when compared to the single-threaded CPU implementation. GPU implementation on a single Nvidia Tesla K20 runs twice as fast as that for the MIC architecture-based Xeon Phi P5110 coprocessor, but also requires considerably more programming effort. Conclusions General purpose GPUs are a mature platform with large amounts of computing power capable of tackling inherently parallel problems, but can prove demanding for the programmer. On the other hand the new MIC architecture, albeit lacking in performance reduces the programming effort and makes it up with a more general architecture suitable for a wider range of problems. PMID:24964802

77 FR 67409 - Self-Regulatory Organizations; The NASDAQ Stock Market LLC; Notice of Filing and Immediate...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-11-09

...), 7410A (Definitions), 7420A (Applicability), 7430A (Synchronization of Member Business Clocks), 7440A... days after the date of the filing, or such shorter time as the Commission may designate if consistent... the proposed rule change, or such shorter time as designated by the Commission. \\11\\ 15 U.S.C. 78s(b...

Decision support in psychiatry – a comparison between the diagnostic outcomes using a computerized decision support system versus manual diagnosis

PubMed Central

Bergman, Lars G; Fors, Uno GH

2008-01-01

Background Correct diagnosis in psychiatry may be improved by novel diagnostic procedures. Computerized Decision Support Systems (CDSS) are suggested to be able to improve diagnostic procedures, but some studies indicate possible problems. Therefore, it could be important to investigate CDSS systems with regard to their feasibility to improve diagnostic procedures as well as to save time. Methods This study was undertaken to compare the traditional 'paper and pencil' diagnostic method SCID1 with the computer-aided diagnostic system CB-SCID1 to ascertain processing time and accuracy of diagnoses suggested. 63 clinicians volunteered to participate in the study and to solve two paper-based cases using either a CDSS or manually. Results No major difference between paper and pencil and computer-supported diagnosis was found. Where a difference was found it was in favour of paper and pencil. For example, a significantly shorter time was found for paper and pencil for the difficult case, as compared to computer support. A significantly higher number of correct diagnoses were found in the diffilt case for the diagnosis 'Depression' using the paper and pencil method. Although a majority of the clinicians found the computer method supportive and easy to use, it took a longer time and yielded fewer correct diagnoses than with paper and pencil. Conclusion This study could not detect any major difference in diagnostic outcome between traditional paper and pencil methods and computer support for psychiatric diagnosis. Where there were significant differences, traditional paper and pencil methods were better than the tested CDSS and thus we conclude that CDSS for diagnostic procedures may interfere with diagnosis accuracy. A limitation was that most clinicians had not previously used the CDSS system under study. The results of this study, however, confirm that CDSS development for diagnostic purposes in psychiatry has much to deal with before it can be used for routine clinical purposes. PMID:18261222

Computer image analysis of etched tracks from ionizing radiation

NASA Technical Reports Server (NTRS)

Blanford, George E.

1994-01-01

I proposed to continue a cooperative research project with Dr. David S. McKay concerning image analysis of tracks. Last summer we showed that we could measure track densities using the Oxford Instruments eXL computer and software that is attached to an ISI scanning electron microscope (SEM) located in building 31 at JSC. To reduce the dependence on JSC equipment, we proposed to transfer the SEM images to UHCL for analysis. Last summer we developed techniques to use digitized scanning electron micrographs and computer image analysis programs to measure track densities in lunar soil grains. Tracks were formed by highly ionizing solar energetic particles and cosmic rays during near surface exposure on the Moon. The track densities are related to the exposure conditions (depth and time). Distributions of the number of grains as a function of their track densities can reveal the modality of soil maturation. As part of a consortium effort to better understand the maturation of lunar soil and its relation to its infrared reflectance properties, we worked on lunar samples 67701,205 and 61221,134. These samples were etched for a shorter time (6 hours) than last summer's sample and this difference has presented problems for establishing the correct analysis conditions. We used computer counting and measurement of area to obtain preliminary track densities and a track density distribution that we could interpret for sample 67701,205. This sample is a submature soil consisting of approximately 85 percent mature soil mixed with approximately 15 percent immature, but not pristine, soil.

A polymorphism in a transporter of testosterone is a determinant of androgen independence in prostate cancer.

PubMed

Sharifi, Nima; Hamada, Akinobu; Sissung, Tristan; Danesi, Romano; Venzon, David; Baum, Caitlin; Gulley, James L; Price, Douglas K; Dahut, William L; Figg, William D

2008-08-05

To determine if patients with advanced prostate cancer carrying a polymorphism that codes for a more active testosterone transporter have less durable responses to androgen-deprivation therapy (ADT) than patients not carrying this polymorphism. We previously determined that a polymorphism in SLCO1B3 affects testosterone transport and that those men who have at least one wild-type T allele at the 334 T > G polymorphism in this gene have a shorter survival. We hypothesized that the T allele which increases testosterone transport would be associated with a shorter interval from ADT to androgen independence. We examined the association between this SLCO1B3 polymorphism and time from ADT to androgen independence, ADT to prostate-specific antigen (PSA) nadir and PSA nadir to androgen independence in 68 Caucasian patients with advanced prostate cancer who were treated with ADT with metastatic disease (D2) or biochemical failure with no metastatic disease (D0). When examined separately, patients in the individual stages tended to have a shorter time to androgen independence with the T allele in the D0 (P = 0.11) and D2 (P = 0.18) groups. Combining these groups and stratifying by stage yielded a statistically significant shorter time to androgen independence with the T allele (P = 0.048). A polymorphism in a transporter that increases testosterone import is associated with a shorter time to androgen independence in patients with prostate cancer who are treated with ADT.

Demonstrating real-time feedback that enhances the performance of measurement sequence with cat states in a cavity

NASA Astrophysics Data System (ADS)

Ofek, N.; Petrenko, A.; Liu, Y.; Vlastakis, B.; Sun, L.; Leghtas, Z.; Heeres, R.; Sliwa, K. M.; Mirrahimi, M.; Jiang, L.; Devoret, M. H.; Schoelkopf, R. J.

2015-03-01

Real-time feedback offers not just the convenience of streamlined data acquisition, but is an essential element in any quantum computational architecture that requires branching based on measurement outcomes. State-preparation, mitigating the effects of qubit decoherence, and recording the trajectories of quantum systems are just a few of the many potential applications of real-time feedback. Photon number parity measurements of cat states in superconducting resonators are a particularly useful platform for demonstrating the clear advantages of having sophisticated feedback schemes to enhance the performance a proposed error-correction protocol [Leghtas et.al. PRL 2013]. In a cQED architecture, where a transmon qubit is coupled to two superconducting cavities, we present a field-programmable gate array (FPGA) device capable of making decisions and calculations with latency times far shorter than the lifetimes of any of the system's constituents. This level of performance opens the door to realizing many complex, previously unfeasible, experiments in superconducting qubit systems.

Asynchronously Coupled Models of Ice Loss from Airless Planetary Bodies

NASA Astrophysics Data System (ADS)

Schorghofer, N.

2016-12-01

Ice is found near the surface of dwarf planet Ceres, in some main belt asteroids, and perhaps in NEOs that will be explored or even mined in future. The simple but important question of how fast ice is lost from airless bodies can present computational challenges. The thermal cycle on the surface repeats on much shorter time-scales than ice retreats; one process acts on the time-scale of hours, the other over billions of years. This multi-scale situation is addressed with asynchronous coupling, where models with different time steps are woven together. The sharp contrast at the retreating ice table is dealt with with explicit interface tracking. For Ceres, which is covered with a thermally insulating dust mantle, desiccation rates are orders of magnitude slower than had been calculated with simpler models. More model challenges remain: The role of impact devolatization and the time-scale for complete desiccation of an asteroid. I will also share my experience with code distribution using GitHub and Zenodo.

Merging taper lengths for short duration lane closure : final report, December 2009.

DOT National Transportation Integrated Search

2009-12-01

The Utility Industry has requested that the Florida Department of Transportation provide for the use of merging taper lengths that are significantly shorter than the lengths computed using the taper length equations published in the MUTCD Section 6C....

Residence time of symmetric random walkers in a strip with large reflective obstacles

NASA Astrophysics Data System (ADS)

Ciallella, Alessandro; Cirillo, Emilio N. M.; Sohier, Julien

2018-05-01

We study the effect of a large obstacle on the so-called residence time, i.e., the time that a particle performing a symmetric random walk in a rectangular (two-dimensional, 2D) domain needs to cross the strip. We observe complex behavior: We find out that the residence time does not depend monotonically on the geometric properties of the obstacle, such as its width, length, and position. In some cases, due to the presence of the obstacle, the mean residence time is shorter with respect to the one measured for the obstacle-free strip. We explain the residence time behavior by developing a one-dimensional (1D) analog of the 2D model where the role of the obstacle is played by two defect sites having smaller probability to be crossed with respect to all the other regular sites. The 1D and 2D models behave similarly, but in the 1D case we are able to compute exactly the residence time, finding a perfect match with the Monte Carlo simulations.

Computer-designed surgical guide template compared with free-hand operation for mesiodens extraction in premaxilla using “trapdoor” method

PubMed Central

Hu, Ying Kai; Xie, Qian Yang; Yang, Chi; Xu, Guang Zhou

2017-01-01

Abstract The aim of this study was to introduce a novel method of mesiodens extraction using a vascularized pedicled bone flap by piezosurgery and to compare the differences between a computer-aided design surgical guide template and free-hand operation. A total of 8 patients with mesiodens, 4 with a surgical guide (group I), and 4 without it (group II) were included in the study. The surgical design was to construct a trapdoor pedicle on the superior mucoperiosteal attachment with application of piezosurgery. The bone lid was repositioned after mesiodens extraction. Group I patients underwent surgeries based on the preoperative planning with surgical guide templates, while group II patients underwent free-hand operation. The outcome variables were success rate, intraoperative time, anterior nasal spine (ANS) position, changes of nasolabial angle (NLA), and major complications. Data from the 2 groups were compared by SPSS 17.0, using Wilcoxon test. The operative time was significantly shorter in group I patients. All the mesiodentes were extracted successfully and no obvious differences of preoperative and postoperative ANS position and NLA value were found in both groups. The patients were all recovered uneventfully. Surgical guide templates can enhance clinical accuracy and reduce operative time by facilitating accurate osteotomies. PMID:28658139

The application of computers to learning in the Command and General Staff College (CGSC): A front end analysis study: CGSC analysis, Task A

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

Thorn, C.T.

1988-01-01

The US Army Command and General Staff College (CGSC) is organized in five schools, one of which, Command and General Staff School (CGSS), is not formally established. These schools provide instruction to officers, noncommissioned officers, and civilians through 4 primary courses and approximately 20 shorter courses. The primary courses are CAS/sup 3/ (Combined Arms and Services Staff School) Phase I Nonresident Course, CAS/sup 3/ Phase II Resident Course, CGSOC (Command and General Staff Officers Course), and SAMS (School of Advanced Military Studies). The shorter courses are primarily provided through SPD (School of Professional Development). Task A analyzed the curricula ofmore » the primary courses in terms of organization and cognitive level with the goal of providing the project team sufficient understanding of the College to seriously address the issue of the application of computers to learning in Task G.« less

Comparison of flexible ureterorenoscopy and mini-percutaneous nephrolithotomy in treatment of lower calyceal stones smaller than 2 cm.

PubMed

Akbulut, Fatih; Kucuktopcu, Onur; Kandemir, Emre; Sonmezay, Erkan; Simsek, Abdulmuttalip; Ozgor, Faruk; Binbay, Murat; Muslumanoglu, Ahmet Yaser; Gurbuz, Gokhan

2016-01-01

To compare the outcomes of flexible ureterorenoscopy (F-URS) and mini-percutaneous nephrolithotomy (mini-PNL) in the treatment of lower calyceal stones smaller than 2 cm. Patients who underwent F-URS and mini-PNL for the treatment of lower calyceal stones smaller than 2 cm between March 2009 and December 2014 were retrospectively evaluated. Ninety-four patients were divided into two groups by treatment modality: F-URS (Group 1: 63 patients) and mini-PNL (Group 2: 31 patients). All patients were preoperatively diagnosed with intravenous pyelography or computed tomography. Success rates for F-URS and mini-PNL at postoperative first month were 85.7% and 90.3%, respectively. Operation time, fluoroscopy time, and hospitalization time for F-URS and mini-PNL patients were 44.40 min, 2.9 min, 22.4 h, and 91.9 min, 6.4 min, and 63.8 h, respectively. All three parameters were significantly shorter among the F-URS group (p < 0.001). Postoperative hemoglobin drop was significantly lower in F-URS group compared to mini-PNL group (0.39 mg/dL vs. 1.15 mg/dL, p = 0.001). A comparison of complications according to the Clavien classification demonstrated significant differences between the groups (p = 0.001). More patients in the F-URS groups require antibiotics due to urinary tract infection, and more patients in the mini-PNL group required ureteral double J catheter insertion under general anesthesia. Although both F-URS and mini-PNL have similar success rates for the treatment of lower calyceal stones, F-URS appears to be more favorable due to shorter fluoroscopy and hospitalization times; and lower hemoglobin drops. Multicenter and studies using higher patient volumes are needed to confirm these findings.

Maternal and fetal effect of misgav ladach cesarean section in nigerian women: a randomized control study.

PubMed

Ezechi, Oc; Ezeobi, Pm; Gab-Okafor, Cv; Edet, A; Nwokoro, Ca; Akinlade, A

2013-10-01

The poor utilisation of the Misgav-Ladach (ML) caesarean section method in our environment despite its proven advantage has been attributed to several factors including its non-evaluation. A well designed and conducted trial is needed to provide evidence to convince clinician of its advantage over Pfannenstiel based methods. To evaluate the outcome of ML based caesarean section among Nigerian women. Randomised controlled open label study of 323 women undergoing primary caesarean section in Lagos Nigeria. The women were randomised to either ML method or Pfannenstiel based (PB) caesarean section technique using computer generated random numbers. The mean duration of surgery (P < 0.001), time to first bowel motion (P = 0.01) and ambulation (P < 0.001) were significantly shorter in the ML group compared to PB group. Postoperative anaemia (P < 0.01), analgesic needs (P = 0.02), extra suture use, estimated blood loss (P < 0.01) and post-operative complications (P = 0.001) were significantly lower in the ML group compared to PB group. Though the mean hospital stay was shorter (5.8 days) in the ML group as against 6.0 days, the difference was not significant statistically (P = 0.17). Of the fetal outcome measures compared, it was only in the fetal extraction time that there was significant difference between the two groups (P = 0.001). The mean fetal extraction time was 162 sec in ML group compared to 273 sec in the PB group. This study confirmed the already established benefit of ML techniques in Nigerian women, as it relates to the postoperative outcomes, duration of surgery, and fetal extraction time. The technique is recommended to clinicians as its superior maternal and fetal outcome and cost saving advantage makes it appropriate for use in poor resource setting.

Transition-Tempered Metadynamics Is a Promising Tool for Studying the Permeation of Drug-like Molecules through Membranes.

PubMed

Sun, Rui; Dama, James F; Tan, Jeffrey S; Rose, John P; Voth, Gregory A

2016-10-11

Metadynamics is an important enhanced sampling technique in molecular dynamics simulation to efficiently explore potential energy surfaces. The recently developed transition-tempered metadynamics (TTMetaD) has been proven to converge asymptotically without sacrificing exploration of the collective variable space in the early stages of simulations, unlike other convergent metadynamics (MetaD) methods. We have applied TTMetaD to study the permeation of drug-like molecules through a lipid bilayer to further investigate the usefulness of this method as applied to problems of relevance to medicinal chemistry. First, ethanol permeation through a lipid bilayer was studied to compare TTMetaD with nontempered metadynamics and well-tempered metadynamics. The bias energies computed from various metadynamics simulations were compared to the potential of mean force calculated from umbrella sampling. Though all of the MetaD simulations agree with one another asymptotically, TTMetaD is able to predict the most accurate and reliable estimate of the potential of mean force for permeation in the early stages of the simulations and is robust to the choice of required additional parameters. We also show that using multiple randomly initialized replicas allows convergence analysis and also provides an efficient means to converge the simulations in shorter wall times and, more unexpectedly, in shorter CPU times; splitting the CPU time between multiple replicas appears to lead to less overall error. After validating the method, we studied the permeation of a more complicated drug-like molecule, trimethoprim. Three sets of TTMetaD simulations with different choices of collective variables were carried out, and all converged within feasible simulation time. The minimum free energy paths showed that TTMetaD was able to predict almost identical permeation mechanisms in each case despite significantly different definitions of collective variables.

Collision lifetimes and impact statistics of near-Earth asteroids

NASA Technical Reports Server (NTRS)

Bottke, W. F., Jr.; Nolan, M. C.; Greenberg, R.

1993-01-01

We have examined the lifetimes of Near-Earth asteroids (NEA's) by directly computing the collision probabilities with other asteroids and with the terrestrial planets. We compare these to the dynamical lifetimes, and to collisional lifetimes assumed by other workers. We discuss the implications of the differences. The lifetimes of NEA's are important because, along with the statistics of craters on the Earth and Moon, they help us to compute the number of NEA's and the rate at which new NEA's are brought to the vicinity of the Earth. Assuming that the NEA population is in steady-state, the lifetimes determine the flux of new bodies needed to replenish the population. Earlier estimates of the lifetimes ignored (or incompletely accounted for) the differences in the velocities of asteroids as they move in their orbits, so our results differ from (for example) Greenberg and Chapman (1983, Icarus 55, 455) and Wetherill (1988, Icarus 76, 1) by factors of 2 to 10. We have computed the collision rates and relative velocities of NEA's with each other, the main-belt asteroids, and the terrestrial planets, using the corrected method described by Bottke et. al. (1992, GRL, in press). We find that NEA's typically have shorter collisional lifetimes than do main-belt asteroids of the same size, due to their high eccentricities, which typically give them aphelia in the main belt. Consequently, they spend a great deal of time in the main belt, and are moving much slower than the bodies around them, making them 'sitting ducks' for impacts with other asteroids. They cross the paths of many objects, and their typical collision velocities are much higher (10-15 km/s) than the collision velocities (5 km/s) among objects within the main belt. These factors combine to give them substantially shorter lifetimes than had been previously estimated.

Real-time processing for full-range Fourier-domain optical-coherence tomography with zero-filling interpolation using multiple graphic processing units.

PubMed

Watanabe, Yuuki; Maeno, Seiya; Aoshima, Kenji; Hasegawa, Haruyuki; Koseki, Hitoshi

2010-09-01

The real-time display of full-range, 2048?axial pixelx1024?lateral pixel, Fourier-domain optical-coherence tomography (FD-OCT) images is demonstrated. The required speed was achieved by using dual graphic processing units (GPUs) with many stream processors to realize highly parallel processing. We used a zero-filling technique, including a forward Fourier transform, a zero padding to increase the axial data-array size to 8192, an inverse-Fourier transform back to the spectral domain, a linear interpolation from wavelength to wavenumber, a lateral Hilbert transform to obtain the complex spectrum, a Fourier transform to obtain the axial profiles, and a log scaling. The data-transfer time of the frame grabber was 15.73?ms, and the processing time, which includes the data transfer between the GPU memory and the host computer, was 14.75?ms, for a total time shorter than the 36.70?ms frame-interval time using a line-scan CCD camera operated at 27.9?kHz. That is, our OCT system achieved a processed-image display rate of 27.23 frames/s.

Efficient constraint handling in electromagnetism-like algorithm for traveling salesman problem with time windows.

PubMed

Yurtkuran, Alkın; Emel, Erdal

2014-01-01

The traveling salesman problem with time windows (TSPTW) is a variant of the traveling salesman problem in which each customer should be visited within a given time window. In this paper, we propose an electromagnetism-like algorithm (EMA) that uses a new constraint handling technique to minimize the travel cost in TSPTW problems. The EMA utilizes the attraction-repulsion mechanism between charged particles in a multidimensional space for global optimization. This paper investigates the problem-specific constraint handling capability of the EMA framework using a new variable bounding strategy, in which real-coded particle's boundary constraints associated with the corresponding time windows of customers, is introduced and combined with the penalty approach to eliminate infeasibilities regarding time window violations. The performance of the proposed algorithm and the effectiveness of the constraint handling technique have been studied extensively, comparing it to that of state-of-the-art metaheuristics using several sets of benchmark problems reported in the literature. The results of the numerical experiments show that the EMA generates feasible and near-optimal results within shorter computational times compared to the test algorithms.

Efficient Constraint Handling in Electromagnetism-Like Algorithm for Traveling Salesman Problem with Time Windows

PubMed Central

Yurtkuran, Alkın

2014-01-01

The traveling salesman problem with time windows (TSPTW) is a variant of the traveling salesman problem in which each customer should be visited within a given time window. In this paper, we propose an electromagnetism-like algorithm (EMA) that uses a new constraint handling technique to minimize the travel cost in TSPTW problems. The EMA utilizes the attraction-repulsion mechanism between charged particles in a multidimensional space for global optimization. This paper investigates the problem-specific constraint handling capability of the EMA framework using a new variable bounding strategy, in which real-coded particle's boundary constraints associated with the corresponding time windows of customers, is introduced and combined with the penalty approach to eliminate infeasibilities regarding time window violations. The performance of the proposed algorithm and the effectiveness of the constraint handling technique have been studied extensively, comparing it to that of state-of-the-art metaheuristics using several sets of benchmark problems reported in the literature. The results of the numerical experiments show that the EMA generates feasible and near-optimal results within shorter computational times compared to the test algorithms. PMID:24723834

Video attention deviation estimation using inter-frame visual saliency map analysis

NASA Astrophysics Data System (ADS)

Feng, Yunlong; Cheung, Gene; Le Callet, Patrick; Ji, Yusheng

2012-01-01

A viewer's visual attention during video playback is the matching of his eye gaze movement to the changing video content over time. If the gaze movement matches the video content (e.g., follow a rolling soccer ball), then the viewer keeps his visual attention. If the gaze location moves from one video object to another, then the viewer shifts his visual attention. A video that causes a viewer to shift his attention often is a "busy" video. Determination of which video content is busy is an important practical problem; a busy video is difficult for encoder to deploy region of interest (ROI)-based bit allocation, and hard for content provider to insert additional overlays like advertisements, making the video even busier. One way to determine the busyness of video content is to conduct eye gaze experiments with a sizable group of test subjects, but this is time-consuming and costineffective. In this paper, we propose an alternative method to determine the busyness of video-formally called video attention deviation (VAD): analyze the spatial visual saliency maps of the video frames across time. We first derive transition probabilities of a Markov model for eye gaze using saliency maps of a number of consecutive frames. We then compute steady state probability of the saccade state in the model-our estimate of VAD. We demonstrate that the computed steady state probability for saccade using saliency map analysis matches that computed using actual gaze traces for a range of videos with different degrees of busyness. Further, our analysis can also be used to segment video into shorter clips of different degrees of busyness by computing the Kullback-Leibler divergence using consecutive motion compensated saliency maps.

Decisions in Motion: Decision Dynamics during Intertemporal Choice reflect Subjective Evaluation of Delayed Rewards

NASA Astrophysics Data System (ADS)

O'Hora, Denis; Carey, Rachel; Kervick, Aoife; Crowley, David; Dabrowski, Maciej

2016-02-01

People tend to discount rewards or losses that occur in the future. Such delay discounting has been linked to many behavioral and health problems, since people choose smaller short-term gains over greater long-term gains. We investigated whether the effect of delays on the subjective value of rewards is expressed in how people move when they make choices. Over 600 patrons of the RISK LAB exhibition hosted by the Science Gallery DublinTM played a short computer game in which they used a computer mouse to choose between amounts of money at various delays. Typical discounting effects were observed and decision dynamics indicated that choosing smaller short-term rewards became easier (i.e., shorter response times, tighter trajectories, less vacillation) as the delays until later rewards increased. Based on a sequence of choices, subjective values of delayed outcomes were estimated and decision dynamics during initial choices predicted these values. Decision dynamics are affected by subjective values of available options and thus provide a means to estimate such values.

Double-multiple streamtube model for Darrieus in turbines

NASA Technical Reports Server (NTRS)

Paraschivoiu, I.

1981-01-01

An analytical model is proposed for calculating the rotor performance and aerodynamic blade forces for Darrieus wind turbines with curved blades. The method of analysis uses a multiple-streamtube model, divided into two parts: one modeling the upstream half-cycle of the rotor and the other, the downstream half-cycle. The upwind and downwind components of the induced velocities at each level of the rotor were obtained using the principle of two actuator disks in tandem. Variation of the induced velocities in the two parts of the rotor produces larger forces in the upstream zone and smaller forces in the downstream zone. Comparisons of the overall rotor performance with previous methods and field test data show the important improvement obtained with the present model. The calculations were made using the computer code CARDAA developed at IREQ. The double-multiple streamtube model presented has two major advantages: it requires a much shorter computer time than the three-dimensional vortex model and is more accurate than multiple-streamtube model in predicting the aerodynamic blade loads.

On a fast calculation of structure factors at a subatomic resolution.

PubMed

Afonine, P V; Urzhumtsev, A

2004-01-01

In the last decade, the progress of protein crystallography allowed several protein structures to be solved at a resolution higher than 0.9 A. Such studies provide researchers with important new information reflecting very fine structural details. The signal from these details is very weak with respect to that corresponding to the whole structure. Its analysis requires high-quality data, which previously were available only for crystals of small molecules, and a high accuracy of calculations. The calculation of structure factors using direct formulae, traditional for 'small-molecule' crystallography, allows a relatively simple accuracy control. For macromolecular crystals, diffraction data sets at a subatomic resolution contain hundreds of thousands of reflections, and the number of parameters used to describe the corresponding models may reach the same order. Therefore, the direct way of calculating structure factors becomes very time expensive when applied to large molecules. These problems of high accuracy and computational efficiency require a re-examination of computer tools and algorithms. The calculation of model structure factors through an intermediate generation of an electron density [Sayre (1951). Acta Cryst. 4, 362-367; Ten Eyck (1977). Acta Cryst. A33, 486-492] may be much more computationally efficient, but contains some parameters (grid step, 'effective' atom radii etc.) whose influence on the accuracy of the calculation is not straightforward. At the same time, the choice of parameters within safety margins that largely ensure a sufficient accuracy may result in a significant loss of the CPU time, making it close to the time for the direct-formulae calculations. The impact of the different parameters on the computer efficiency of structure-factor calculation is studied. It is shown that an appropriate choice of these parameters allows the structure factors to be obtained with a high accuracy and in a significantly shorter time than that required when using the direct formulae. Practical algorithms for the optimal choice of the parameters are suggested.

Discrimination in waiting times by insurance type and financial soundness of German acute care hospitals.

PubMed

Schwierz, Christoph; Wübker, Achim; Wübker, Ansgar; Kuchinke, Björn A

2011-10-01

This paper shows that patients with private health insurance (PHI) are being offered significantly shorter waiting times than patients with statutory health insurance (SHI) in German acute hospital care. This behavior may be driven by the higher expected profitability of PHI relative to SHI holders. Further, we find that hospitals offering private insurees shorter waiting times when compared with SHI holders have a significantly better financial performance than those abstaining from or with less discrimination.

A Structured-Inquiry Approach to Teaching Neurophysiology Using Computer Simulation

PubMed Central

Crisp, Kevin M.

2012-01-01

Computer simulation is a valuable tool for teaching the fundamentals of neurophysiology in undergraduate laboratories where time and equipment limitations restrict the amount of course content that can be delivered through hands-on interaction. However, students often find such exercises to be tedious and unstimulating. In an effort to engage students in the use of computational modeling while developing a deeper understanding of neurophysiology, an attempt was made to use an educational neurosimulation environment as the basis for a novel, inquiry-based research project. During the semester, students in the class wrote a research proposal, used the Neurodynamix II simulator to generate a large data set, analyzed their modeling results statistically, and presented their findings at the Midbrains Neuroscience Consortium undergraduate poster session. Learning was assessed in the form of a series of short term papers and two 10-min in-class writing responses to the open-ended question, “How do ion channels influence neuronal firing?”, which they completed on weeks 6 and 15 of the semester. Students’ answers to this question showed a deeper understanding of neuronal excitability after the project; their term papers revealed evidence of critical thinking about computational modeling and neuronal excitability. Suggestions for the adaptation of this structured-inquiry approach into shorter term lab experiences are discussed. PMID:23494064

A characterization of persistence at short times in the WFC3/IR detector

NASA Astrophysics Data System (ADS)

Gennaro, M.; Bajaj, V.; Long, K.

2018-05-01

Persistence in the WFC3/IR detector appears to decay as a power law as a function of time elapsed since the end of a stimulus. In this report we study departures from the power law at times shorter than a few hundreds seconds after the stimulus. In order to have better short-time cadence, we use the Multiaccum (.ima) files, which trace the accumulated charge in the pixels as function of time, rather than the final pipeline products (.flt files), which instead report the electron rate estimated via a linear fit to the accumulated charge vs. time relation. We note that at short times after the stimulus, the absolute change in persistence is the strongest, thus a linear fit to the accumulated signal (the .flt values) can be a poor representation of the strongly varying persistence signal. The already observed power-law decay of the persistence signal, still holds at shorter times, with typical values of the power law index, gamma in [-0.8,-1] for stimuli that saturate the WFC3 pixels. To a good degree of approximation, a single power law is a good fit to the persistence signal decay from 100 to 5000 seconds. We also detect a tapering-off in the power-law decay at increasingly shorter times. This change in behavior is of the order of Delta Gamma 0.02 - 0.05 when comparing power-law fits performed to the persistence signal from 0 up to 250 seconds and from 0 up to 4000 seconds after the stimulus, indicating that persistence decays slightly more rapidly as time progresses. Our results may suggest that for even shorter times, not probed by our study, the WFC3 persistence signal might deviate from a single power-law model.

[A comparison of laparoscopic versus open repair for the surgical treatment of perforated peptic ulcers].

PubMed

Domínguez-Vega, Gerardo; Pera, Manuel; Ramón, José M; Puig, Sonia; Membrilla, Estela; Sancho, Joan; Grande, Luis

2013-01-01

To analyse the outcomes of laparoscopic versus open repair for perforated peptic ulcers (PPU). All patients undergoing PPU repair between January 2002 and March 2012 were included in the study. Demographic characteristics, operation time, complications, and length of hospital stay were evaluated. Two hundred and twelve patients (median age, 49 years) were included, 60 in the laparoscopic group and 52 in the open group. Patients operated laparoscopically were significantly younger and had a higher consumption of tobacco, alcohol and cannabis. Median acute symptoms time was shorter in the laparoscopic group (6h) compared to the open group (12h; P=.025) Symptoms time was shorter in the laparoscopic group. Median operating time was significantly longer in the laparoscopic group (104.5min vs. 76min, P=.025). The percentage of conversion to open repair was 25%. There was no difference in morbidity between 2 groups, but there were 3 deaths in the open group. Median hospital stay was significantly shorter in patients treated laparoscopically when compared with the open group (6 days vs. 8 days; P=.041). Laparoscopic and open repair are equally safe in the management of PPU. A shorter hospital stay can be achieved in the laparoscopic group. Copyright © 2012 AEC. Published by Elsevier Espana. All rights reserved.

Optimizing distance-based methods for large data sets

NASA Astrophysics Data System (ADS)

Scholl, Tobias; Brenner, Thomas

2015-10-01

Distance-based methods for measuring spatial concentration of industries have received an increasing popularity in the spatial econometrics community. However, a limiting factor for using these methods is their computational complexity since both their memory requirements and running times are in {{O}}(n^2). In this paper, we present an algorithm with constant memory requirements and shorter running time, enabling distance-based methods to deal with large data sets. We discuss three recent distance-based methods in spatial econometrics: the D&O-Index by Duranton and Overman (Rev Econ Stud 72(4):1077-1106, 2005), the M-function by Marcon and Puech (J Econ Geogr 10(5):745-762, 2010) and the Cluster-Index by Scholl and Brenner (Reg Stud (ahead-of-print):1-15, 2014). Finally, we present an alternative calculation for the latter index that allows the use of data sets with millions of firms.

Evaluation of a Magneto-optical Filter and a Fabry-perot Interferometer for the Measurement of Solar Velocity Fields from Space

NASA Technical Reports Server (NTRS)

Rhodes, E. J., Jr.; Cacciani, A.; Blamont, J.; Tomczyk, S.; Ulrich, R. K.; Howard, R. F.

1984-01-01

A program was developed to evaluate the performance of three different devices as possible space-borne solar velocity field imagers. Two of these three devices, a magneto-optical filter and a molecular adherence Fabry-Perot interferometer were installed in a newly-constructed observing system located at the 60-foot tower telescope at the Mt. Wilson Observatory. Time series of solar filtergrams and Dopplergrams lasting up to 10 hours per day were obtained with the filter while shorter runs were obtained with the Fabry-Perot. Two-dimensional k (sub h)-omega power spectra which show clearly the well-known p-mode ridges were computed from the time series obtained with the magneto-optical filter. These power spectra were compared with similar power spectra obtained recently with the 13.7-m McMath spectrograph at Kitt Peak.

Computer aided detection system for Osteoporosis using low dose thoracic 3D CT images

NASA Astrophysics Data System (ADS)

Tsuji, Daisuke; Matsuhiro, Mikio; Suzuki, Hidenobu; Kawata, Yoshiki; Niki, Noboru; Nakano, Yasutaka; Harada, Masafumi; Kusumoto, Masahiko; Tsuchida, Takaaki; Eguchi, Kenji; Kaneko, Masahiro

2018-02-01

The patient of osteoporosis is about 13 million people in Japan and it is one of healthy life problems in the aging society. It is necessary to do early stage detection and treatment in order to prevent the osteoporosis. Multi-slice CT technology has been improving the three dimensional (3D) image analysis with higher resolution and shorter scan time. The 3D image analysis of thoracic vertebra can be used for supporting to diagnosis of osteoporosis. This analysis can be used for lung cancer detection at the same time. We develop method of shape analysis and CT values of spongy bone for the detection osteoporosis. Osteoporosis and lung cancer screening show high extraction rate by the thoracic vertebral evaluation CT images. In addition, we created standard pattern of CT value per thoracic vertebra for male age group using 298 low dose data.

Do Athletes Excel at Everyday Tasks?

PubMed Central

CHADDOCK, LAURA; NEIDER, MARK B.; VOSS, MICHELLE W.; GASPAR, JOHN G.; KRAMER, ARTHUR F.

2014-01-01

Purpose Cognitive enhancements are associated with sport training. We extended the sport-cognition literature by using a realistic street crossing task to examine the multitasking and processing speed abilities of collegiate athletes and nonathletes. Methods Pedestrians navigated trafficked roads by walking on a treadmill in a virtual world, a challenge that requires the quick and simultaneous processing of multiple streams of information. Results Athletes had higher street crossing success rates than nonathletes, as reflected by fewer collisions with moving vehicles. Athletes also showed faster processing speed on a computer-based test of simple reaction time, and shorter reaction times were associated with higher street crossing success rates. Conclusions The results suggest that participation in athletics relates to superior street crossing multitasking abilities and that athlete and nonathlete differences in processing speed may underlie this difference. We suggest that cognitive skills trained in sport may transfer to performance on everyday fast-paced multitasking abilities. PMID:21407125

Computer-aided diagnosis for osteoporosis using chest 3D CT images

NASA Astrophysics Data System (ADS)

Yoneda, K.; Matsuhiro, M.; Suzuki, H.; Kawata, Y.; Niki, N.; Nakano, Y.; Ohmatsu, H.; Kusumoto, M.; Tsuchida, T.; Eguchi, K.; Kaneko, M.

2016-03-01

The patients of osteoporosis comprised of about 13 million people in Japan and it is one of the problems the aging society has. In order to prevent the osteoporosis, it is necessary to do early detection and treatment. Multi-slice CT technology has been improving the three dimensional (3-D) image analysis with higher body axis resolution and shorter scan time. The 3-D image analysis using multi-slice CT images of thoracic vertebra can be used as a support to diagnose osteoporosis and at the same time can be used for lung cancer diagnosis which may lead to early detection. We develop automatic extraction and partitioning algorithm for spinal column by analyzing vertebral body structure, and the analysis algorithm of the vertebral body using shape analysis and a bone density measurement for the diagnosis of osteoporosis. Osteoporosis diagnosis support system obtained high extraction rate of the thoracic vertebral in both normal and low doses.

On the Use of Parmetric-CAD Systems and Cartesian Methods for Aerodynamic Design

NASA Technical Reports Server (NTRS)

Nemec, Marian; Aftosmis, Michael J.; Pulliam, Thomas H.

2004-01-01

Automated, high-fidelity tools for aerodynamic design face critical issues in attempting to optimize real-life geometry arid in permitting radical design changes. Success in these areas promises not only significantly shorter design- cycle times, but also superior and unconventional designs. To address these issues, we investigate the use of a parmetric-CAD system in conjunction with an embedded-boundary Cartesian method. Our goal is to combine the modeling capabilities of feature-based CAD with the robustness and flexibility of component-based Cartesian volume-mesh generation for complex geometry problems. We present the development of an automated optimization frame-work with a focus on the deployment of such a CAD-based design approach in a heterogeneous parallel computing environment.

Faculty and student expectations and perceptions of e-mail communication in a campus and distance doctor of pharmacy program.

PubMed

Foral, Pamela A; Turner, Paul D; Monaghan, Michael S; Walters, Ryan W; Merkel, Jennifer J; Lipschultz, Jeremy H; Lenz, Thomas L

2010-12-15

To examine faculty members' and students' expectations and perceptions of e-mail communication in a dual pathway pharmacy program. Three parallel survey instruments were administered to campus students, distance students, and faculty members, respectively. Focus groups with students and faculty were conducted. Faculty members perceived themselves as more accessible and approachable by e-mail than either group of students did. Campus students expected a shorter faculty response time to e-mail and for faculty members to be more available than did distance students. E-mail is an effective means of computer-mediated communication between faculty members and students and can be used to promote a sense of community and inclusiveness (ie, immediacy), especially with distant students.

Sort entropy-based for the analysis of EEG during anesthesia

NASA Astrophysics Data System (ADS)

Ma, Liang; Huang, Wei-Zhi

2010-08-01

The monitoring of anesthetic depth is an absolutely necessary procedure in the process of surgical operation. To judge and control the depth of anesthesia has become a clinical issue which should be resolved urgently. EEG collected wiil be processed by sort entrop in this paper. Signal response of the surface of the cerebral cortex is determined for different stages of patients in the course of anesthesia. EEG is simulated and analyzed through the fast algorithm of sort entropy. The results show that discipline of phasic changes for EEG is very detected accurately,and it has better noise immunity in detecting the EEG anaesthetized than approximate entropy. In conclusion,the computing of Sort entropy algorithm requires shorter time. It has high efficiency and strong anti-interference.

Reduction in patient burdens with graphical computerized adaptive testing on the ADL scale: tool development and simulation

PubMed Central

Chien, Tsair-Wei; Wu, Hing-Man; Wang, Weng-Chung; Castillo, Roberto Vasquez; Chou, Willy

2009-01-01

Background The aim of this study was to verify the effectiveness and efficacy of saving time and reducing burden for patients, nurses, and even occupational therapists through computer adaptive testing (CAT). Methods Based on an item bank of the Barthel Index (BI) and the Frenchay Activities Index (FAI) for assessing comprehensive activities of daily living (ADL) function in stroke patients, we developed a visual basic application (VBA)-Excel CAT module, and (1) investigated whether the averaged test length via CAT is shorter than that of the traditional all-item-answered non-adaptive testing (NAT) approach through simulation, (2) illustrated the CAT multimedia on a tablet PC showing data collection and response errors of ADL clinical functional measures in stroke patients, and (3) demonstrated the quality control of endorsing scale with fit statistics to detect responding errors, which will be further immediately reconfirmed by technicians once patient ends the CAT assessment. Results The results show that endorsed items could be shorter on CAT (M = 13.42) than on NAT (M = 23) at 41.64% efficiency in test length. However, averaged ability estimations reveal insignificant differences between CAT and NAT. Conclusion This study found that mobile nursing services, placed at the bedsides of patients could, through the programmed VBA-Excel CAT module, reduce the burden to patients and save time, more so than the traditional NAT paper-and-pencil testing appraisals. PMID:19416521

Transperitoneal approach versus retroperitoneal approach: a meta-analysis of laparoscopic partial nephrectomy for renal cell carcinoma.

PubMed

Ren, Tong; Liu, Yan; Zhao, Xiaowen; Ni, Shaobin; Zhang, Cheng; Guo, Changgang; Ren, Minghua

2014-01-01

To compare the efficiency and safety of the transperitoneal approaches with retroperitoneal approaches in laparoscopic partial nephrectomy for renal cell carcinoma and provide evidence-based medicine support for clinical treatment. A systematic computer search of PUBMED, EMBASE, and the Cochrane Library was executed to identify retrospective observational and prospective randomized controlled trials studies that compared the outcomes of the two approaches in laparoscopic partial nephrectomy. Two reviewers independently screened, extracted, and evaluated the included studies and executed statistical analysis by using software STATA 12.0. Outcomes of interest included perioperative and postoperative variables, surgical complications and oncological variables. There were 8 studies assessed transperitoneal laparoscopic partial nephrectomy (TLPN) versus retroperitoneal laparoscopic partial nephrectomy (RLPN) were included. RLPN had a shorter operating time (SMD = 1.001,95%confidence interval[CI] 0.609-1.393,P<0.001), a lower estimated blood loss (SMD = 0.403,95%CI 0.015-0.791,P = 0.042) and a shorter length of hospital stay (WMD = 0.936 DAYS,95%CI 0.609-1.263,P<0.001) than TLPN. There were no significant differences between the transperitoneal and retroperitoneal approaches in other outcomes of interest. This meta-analysis indicates that, in appropriately selected patients, especially patients with intraperitoneal procedures history or posteriorly located renal tumors, the RLPN can shorten the operation time, reduce the estimated blood loss and shorten the length of hospital stay. RLPN may be equally safe and be faster compared with the TLPN.

The limited role of recombination energy in common envelope removal

NASA Astrophysics Data System (ADS)

Grichener, Aldana; Sabach, Efrat; Soker, Noam

2018-05-01

We calculate the outward energy transport time by convection and photon diffusion in an inflated common envelope and find this time to be shorter than the envelope expansion time. We conclude therefore that most of the hydrogen recombination energy ends in radiation rather than in kinetic energy of the outflowing envelope. We use the stellar evolution code MESA and inject energy inside the envelope of an asymptotic giant branch star to mimic energy deposition by a spiraling-in stellar companion. During 1.7 years the envelope expands by a factor of more than 2. Along the entire evolution the convection can carry the energy very efficiently outwards, to the radius where radiative transfer becomes more efficient. The total energy transport time stays within several months, shorter than the dynamical time of the envelope. Had we included rapid mass loss, as is expected in the common envelope evolution, the energy transport time would have been even shorter. It seems that calculations that assume that most of the recombination energy ends in the outflowing gas might be inaccurate.

An effective support system of emergency medical services with tablet computers.

PubMed

Yamada, Kosuke C; Inoue, Satoshi; Sakamoto, Yuichiro

2015-02-27

There were over 5,000,000 ambulance dispatches during 2010 in Japan, and the time for transportation has been increasing, it took over 37 minutes from dispatch to the hospitals. A way to reduce transportation time by ambulance is to shorten the time of searching for an appropriate facility/hospital during the prehospital phase. Although the information system of medical institutions and emergency medical service (EMS) was established in 2003 in Saga Prefecture, Japan, it has not been utilized efficiently. The Saga Prefectural Government renewed the previous system in an effort to make it the real-time support system that can efficiently manage emergency demand and acceptance for the first time in Japan in April 2011. The objective of this study was to evaluate if the new system promotes efficient emergency transportation for critically ill patients and provides valuable epidemiological data. The new system has provided both emergency personnel in the ambulance, or at the scene, and the medical staff in each hospital to be able to share up-to-date information about available hospitals by means of cloud computing. All 55 ambulances in Saga are equipped with tablet computers through third generation/long term evolution networks. When the emergency personnel arrive on the scene and discern the type of patient's illness, they can search for an appropriate facility/hospital with their tablet computer based on the patient's symptoms and available medical specialists. Data were collected prospectively over a three-year period from April 1, 2011 to March 31, 2013. The transportation time by ambulance in Saga was shortened for the first time since the statistics were first kept in 1999; the mean time was 34.3 minutes in 2010 (based on administrative statistics) and 33.9 minutes (95% CI 33.6-34.1) in 2011. The ratio of transportation to the tertiary care facilities in Saga has decreased by 3.12% from the year before, 32.7% in 2010 (regional average) and 29.58% (9085/30,709) in 2011. The system entry completion rate by the emergency personnel was 100.00% (93,110/93,110) and by the medical staff was 46.11% (14,159/30,709) to 47.57% (14,639/30,772) over a three-year period. Finally, the new system reduced the operational costs by 40,000,000 yen (about $400,000 US dollars) a year. The transportation time by ambulance was shorter following the implementation of the tablet computer in the current support system of EMS in Saga Prefecture, Japan. The cloud computing reduced the cost of the EMS system.

Transient three-dimensional startup side load analysis of a regeneratively cooled nozzle

NASA Astrophysics Data System (ADS)

Wang, Ten-See

2009-07-01

The objective of this effort is to develop a computational methodology to capture the side load physics and to anchor the computed aerodynamic side loads with the available data by simulating the startup transient of a regeneratively cooled, high-aspect-ratio nozzle, hot-fired at sea level. The computational methodology is based on an unstructured-grid, pressure-based, reacting flow computational fluid dynamics and heat transfer formulation, and a transient inlet history based on an engine system simulation. Emphases were put on the effects of regenerative cooling on shock formation inside the nozzle, and ramp rate on side load reduction. The results show that three types of asymmetric shock physics incur strong side loads: the generation of combustion wave, shock transitions, and shock pulsations across the nozzle lip, albeit the combustion wave can be avoided with sparklers during hot-firing. Results from both regenerative cooled and adiabatic wall boundary conditions capture the early shock transitions with corresponding side loads matching the measured secondary side load. It is theorized that the first transition from free-shock separation to restricted-shock separation is caused by the Coanda effect. After which the regeneratively cooled wall enhances the Coanda effect such that the supersonic jet stays attached, while the hot adiabatic wall fights off the Coanda effect, and the supersonic jet becomes detached most of the time. As a result, the computed peak side load and dominant frequency due to shock pulsation across the nozzle lip associated with the regeneratively cooled wall boundary condition match those of the test, while those associated with the adiabatic wall boundary condition are much too low. Moreover, shorter ramp time results show that higher ramp rate has the potential in reducing the nozzle side loads.

[A pilot clinical study of immediate provisionalization with a chairside computer aided design and computer aided manufacture monolithic crown for single tooth immediate implant placement].

PubMed

Tian, J H; Di, P; Lin, Y; Zhang, Y; Wei, D H; Cui, H Y

2017-01-09

Objective: To evaluate the primary clinical outcomes of immediate provisionalization with a monolithic crown utilizing a novel chairside computer aided design and computer aided manufacture (CAD/CAM) workflow for single tooth immediate implant placement. Methods: This pilot study was a prospective within-subjects design. Thirteen consecutive patients were included and diagnosed with untreatable single incisor or premolar with fine general and local anatomical conditions. The trial was conducted at Department of Implantology, Peking University School and Hospital of Stomatology, Beijing, between January 2016 and June 2016. The teeth were extracted atraumatically and implants were immediately placed in the fresh sockets. Two screw-retained interim crowns were fabricated for the same site utilizing different workflows, a monolithic lithium disilicate (LS2) crown produced by CEREC (Sirona, Germany) chairside CAD/CAM system (CER group) and a manually fabricated resin crown utilizing conventional workflow (CONV group) respectively. The patients were blinded to the group allocation of the two interim crowns. After the clinical try-in for both crowns in a randomized sequence, the patients ' level of satisfaction was assessed with a virtual analogue scale (VAS) questionnaire. The restorations chosen by patients themselves were seated in the implants by one experienced prosthodontist. The accuracy, aesthetic effect and clinical time consumption of both groups were compared. Statistical analyses were performed with the Wilcoxon signed rank test. Results: All patients were treated with atraumatic tooth extraction, immediate implant placement using flapless surgery and immediate provisionalization in a single visit. The interim crowns of both groups could be fitted with or without slight adjustments. For each patient, the interim crown of CER group was chosen to be seated with a relatively higher VAS result. The white esthetic score (WES) results demonstrated no statistically significant difference between CER group (7.5±1.1) and CONV group (7.9±0.9) ( P> 0.05). The mean total work time was significantly different resulting in (131.9±5.0) min for CER group and (205.2±6.3) min( P< 0.05). The major difference lied in the laboratory work time, resulting in (113.5±6.3) min for CER group which was significantly shorter than (185.6±6.6) min for CONV group. As for impression taking time, the CER group (7.5±0.8) min was significantly shorter than CONV group (11.7± 1.1) min ( P< 0.05). However, analysis for clinical adjustment time showed a significantly longer time for CER group [(11.0±2.1) min vs (8.0±2.8) min, P< 0.05]. After 3-6 months of observation, the overall survival rate was 100%. Screw loosening occurred in 4 patients and was tightened again. No other major complication soccurred. Conclusions: The full digital workflow utilizing CEREC chairside CAD/CAM system to fabricate interim crowns after immediate implant placement in one single visit was feasible. It was more time-efficient and could effectively shorten the laboratory work time compared to the conventional workflow. Patients demonstrated high satisfaction and there was no statistical difference in WES results compared to the conventional workflow. Favorable clinical outcomes were gained in this short-term follow-up study.

A Design Problem of Assembly Line Systems using Genetic Algorithm under the BTO Environment

NASA Astrophysics Data System (ADS)

Abe, Kazuaki; Yamada, Tetsuo; Matsui, Masayuki

Under the BTO environment, stochastic assembly lines require design methods which shorten not only the production lead time but also the ready time for the line design. We propose a design method for Assembly Line Systems (ALS) in Yamada et al. (2001) by using Genetic Algorithm (GA) and Adam-Eve GA, in which all design variables are determined in consideration of constraints such as line length related to the production lead time. First, an ALS model with a line length constraint is introduced, and an optimal design problem is set to maximize the net reward under shorter lead time. Next, a simulation optimization method is developed using Adam-Eve GA and traditional GA. Finally, an optimal design example is shown and discussed by comparing the 2-stage design by Yamada et al. (2001) and both the GA designs. It is shown that the Adam-Eve GA is superior to the traditional GA design in terms of computational time though there is only a slight difference in terms of net reward.

Tetrahedral and polyhedral mesh evaluation for cerebral hemodynamic simulation--a comparison.

PubMed

Spiegel, Martin; Redel, Thomas; Zhang, Y; Struffert, Tobias; Hornegger, Joachim; Grossman, Robert G; Doerfler, Arnd; Karmonik, Christof

2009-01-01

Computational fluid dynamic (CFD) based on patient-specific medical imaging data has found widespread use for visualizing and quantifying hemodynamics in cerebrovascular disease such as cerebral aneurysms or stenotic vessels. This paper focuses on optimizing mesh parameters for CFD simulation of cerebral aneurysms. Valid blood flow simulations strongly depend on the mesh quality. Meshes with a coarse spatial resolution may lead to an inaccurate flow pattern. Meshes with a large number of elements will result in unnecessarily high computation time which is undesirable should CFD be used for planning in the interventional setting. Most CFD simulations reported for these vascular pathologies have used tetrahedral meshes. We illustrate the use of polyhedral volume elements in comparison to tetrahedral meshing on two different geometries, a sidewall aneurysm of the internal carotid artery and a basilar bifurcation aneurysm. The spatial mesh resolution ranges between 5,119 and 228,118 volume elements. The evaluation of the different meshes was based on the wall shear stress previously identified as a one possible parameter for assessing aneurysm growth. Polyhedral meshes showed better accuracy, lower memory demand, shorter computational speed and faster convergence behavior (on average 369 iterations less).

Group Velocity Dispersion Curves from Wigner-Ville Distributions

NASA Astrophysics Data System (ADS)

Lloyd, Simon; Bokelmann, Goetz; Sucic, Victor

2013-04-01

With the widespread adoption of ambient noise tomography, and the increasing number of local earthquakes recorded worldwide due to dense seismic networks and many very dense temporary experiments, we consider it worthwhile to evaluate alternative Methods to measure surface wave group velocity dispersions curves. Moreover, the increased computing power of even a simple desktop computer makes it feasible to routinely use methods other than the typically employed multiple filtering technique (MFT). To that end we perform tests with synthetic and observed seismograms using the Wigner-Ville distribution (WVD) frequency time analysis, and compare dispersion curves measured with WVD and MFT with each other. Initial results suggest WVD to be at least as good as MFT at measuring dispersion, albeit at a greater computational expense. We therefore need to investigate if, and under which circumstances, WVD yields better dispersion curves than MFT, before considering routinely applying the method. As both MFT and WVD generally work well for teleseismic events and at longer periods, we explore how well the WVD method performs at shorter periods and for local events with smaller epicentral distances. Such dispersion information could potentially be beneficial for improving velocity structure resolution within the crust.

Tidal Interaction among Red Giants Close Binary Systems in APOGEE Database

NASA Astrophysics Data System (ADS)

Sun, Meng; Arras, Phil; Majewski, Steven R.; Troup, Nicholas William; Weinberg, Nevin N.

2017-01-01

Motivated by the newly discovered close binary systems in the Apache Point Observatory Galactic Evolution Experiment (APOGEE-1), the tidal evolution of binaries containing a red giant branch (RGB) star with a stellar or substellar companion was investigated. The tide raised by the companion in the RGB star leads to exchange of angular momentum between the orbit and the stellar spin, causing the orbit to contract. The tidal dissipation rate is computed using turbulent viscosity acting on the equilibrium tidal flow, where careful attention is paid to the effects of reduced viscosity for close-in companions. Evolutionary models for the RGB stars, from the zero-age main sequence to the present, were acquired from the MESA code. "Standard" turbulent viscosity gives rise to such a large orbital decay that many observed systems have decay times much shorter than the RGB evolution time. Several theories for "reduced" turbulent viscosity are investigated, and reduce the number of systems with uncomfortably short decay times.

Minimizing calibration time using inter-subject information of single-trial recognition of error potentials in brain-computer interfaces.

PubMed

Iturrate, Iñaki; Montesano, Luis; Chavarriaga, Ricardo; del R Millán, Jose; Minguez, Javier

2011-01-01

One of the main problems of both synchronous and asynchronous EEG-based BCIs is the need of an initial calibration phase before the system can be used. This phase is necessary due to the high non-stationarity of the EEG, since it changes between sessions and users. The calibration process limits the BCI systems to scenarios where the outputs are very controlled, and makes these systems non-friendly and exhausting for the users. Although it has been studied how to reduce calibration time for asynchronous signals, it is still an open issue for event-related potentials. Here, we propose the minimization of the calibration time on single-trial error potentials by using classifiers based on inter-subject information. The results show that it is possible to have a classifier with a high performance from the beginning of the experiment, and which is able to adapt itself making the calibration phase shorter and transparent to the user.

Simulation of Near-Edge X-ray Absorption Fine Structure with Time-Dependent Equation-of-Motion Coupled-Cluster Theory.

PubMed

Nascimento, Daniel R; DePrince, A Eugene

2017-07-06

An explicitly time-dependent (TD) approach to equation-of-motion (EOM) coupled-cluster theory with single and double excitations (CCSD) is implemented for simulating near-edge X-ray absorption fine structure in molecular systems. The TD-EOM-CCSD absorption line shape function is given by the Fourier transform of the CCSD dipole autocorrelation function. We represent this transform by its Padé approximant, which provides converged spectra in much shorter simulation times than are required by the Fourier form. The result is a powerful framework for the blackbox simulation of broadband absorption spectra. K-edge X-ray absorption spectra for carbon, nitrogen, and oxygen in several small molecules are obtained from the real part of the absorption line shape function and are compared with experiment. The computed and experimentally obtained spectra are in good agreement; the mean unsigned error in the predicted peak positions is only 1.2 eV. We also explore the spectral signatures of protonation in these molecules.

78 FR 78779 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Revisions to Headboat Reporting...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-12-27

... revisions require fishing records to be submitted electronically (via computer or internet) on a weekly basis or at intervals shorter than a week if notified by the NMFS' Southeast Fisheries Science Center (SEFSC) Science and Research Director (SRD), and prohibits [[Page 78780

Relationship Between Final Performance and Block Times with the Traditional and the New Starting Platforms with A Back Plate in International Swimming Championship 50-M and 100-M Freestyle Events

PubMed Central

Garcia-Hermoso, Antonio; Escalante, Yolanda; Arellano, Raul; Navarro, Fernando; Domínguez, Ana M.; Saavedra, Jose M.

2013-01-01

The purpose of this study was to investigate the association between block time and final performance for each sex in 50-m and 100-m individual freestyle, distinguishing between classification (1st to 3rd, 4th to 8th, 9th to 16th) and type of starting platform (old and new) in international competitions. Twenty-six international competitions covering a 13-year period (2000-2012) were analysed retrospectively. The data corresponded to a total of 1657 swimmers’ competition histories. A two-way ANOVA (sex x classification) was performed for each event and starting platform with the Bonferroni post-hoc test, and another two-way ANOVA for sex and starting platform (sex x starting platform). Pearson’s simple correlation coefficient was used to determine correlations between the block time and the final performance. Finally, a simple linear regression analysis was done between the final time and the block time for each sex and platform. The men had shorter starting block times than the women in both events and from both platforms. For 50-m event, medalists had shorter block times than semi- finalists with the old starting platforms. Block times were directly related to performance with the old starting platforms. With the new starting platforms, however, the relationship was inverse, notably in the women’s 50-m event. The block time was related for final performance in the men’s 50- m event with the old starting platform, but with the new platform it was critical only for the women’s 50-m event. Key Points The men had shorter block times than the women in both events and with both platforms. For both distances, the swimmers had shorter block times in their starts from the new starting platform with a back plate than with the old platform. For the 50-m event with the old starting platform, the medalists had shorter block times than the semi-finalists. The new starting platform block time was only determinant in the women’s 50-m event. In order to improve performance, specific training with the new platform with a back plate should be considered. PMID:24421729

Oceanic signals in rapid polar motion: results from a barotropic forward model with explicit consideration of self-attraction and loading effects

NASA Astrophysics Data System (ADS)

Schindelegger, Michael; Quinn, Katherine J.; Ponte, Rui M.

2017-04-01

Numerical modeling of non-tidal variations in ocean currents and bottom pressure has played a key role in closing the excitation budget of Earth's polar motion for a wide range of periodicities. Non-negligible discrepancies between observations and model accounts of pole position changes prevail, however, on sub-monthly time scales and call for examination of hydrodynamic effects usually omitted in general circulation models. Specifically, complete hydrodynamic cores must incorporate self-attraction and loading (SAL) feedbacks on redistributed water masses, effects that produces ocean bottom pressure perturbations of typically about 10% relative to the computed mass variations. Here, we report on a benchmark simulation with a near-global, barotropic forward model forced by wind stress, atmospheric pressure, and a properly calculated SAL term. The latter is obtained by decomposing ocean mass anomalies on a 30-minute grid into spherical harmonics at each time step and applying Love numbers to account for seafloor deformation and changed gravitational attraction. The increase in computational time at each time step is on the order of 50%. Preliminary results indicate that the explicit consideration of SAL in the forward runs increases the fidelity of modeled polar motion excitations, in particular on time scales shorter than 5 days as evident from cross spectral comparisons with geodetic excitation. Definite conclusions regarding the relevance of SAL in simulating rapid polar motion are, however, still hampered by the model's incomplete domain representation that excludes parts of the highly energetic Arctic Ocean.

Circadian course of the P300 ERP in patients with amyotrophic lateral sclerosis - implications for brain-computer interfaces (BCI).

PubMed

Erlbeck, Helena; Mochty, Ursula; Kübler, Andrea; Real, Ruben G L

2017-01-07

Accidents or neurodegenerative diseases like amyotrophic lateral sclerosis (ALS) can lead to progressing, extensive, and complete paralysis leaving patients aware but unable to communicate (locked-in state). Brain-computer interfaces (BCI) based on electroencephalography represent an important approach to establish communication with these patients. The most common BCI for communication rely on the P300, a positive deflection arising in response to rare events. To foster broader application of BCIs for restoring lost function, also for end-users with impaired vision, we explored whether there were specific time windows during the day in which a P300 driven BCI should be preferably applied. The present study investigated the influence of time of the day and modality (visual vs. auditory) on P300 amplitude and latency. A sample of 14 patients (end-users) with ALS and 14 healthy age matched volunteers participated in the study and P300 event-related potentials (ERP) were recorded at four different times (10, 12 am, 2, & 4 pm) during the day. Results indicated no differences in P300 amplitudes or latencies between groups (ALS patients v. healthy participants) or time of measurement. In the auditory condition, latencies were shorter and amplitudes smaller as compared to the visual condition. Our findings suggest applicability of EEG/BCI sessions in patients with ALS throughout normal waking hours. Future studies using actual BCI systems are needed to generalize these findings with regard to BCI effectiveness/efficiency and other times of day.

Potential sulfur-free pulping methods

Treesearch

Edward L. Springer; Rajai H. Atalla; Richard S. Reiner

2002-01-01

Lodgepole pine chips were pulped to Kappa numbers of about 70 using soda–AQ, soda–ODiMAQ, and kraft methods. At a catalyst level of 0.20% (oven-dry wood basis), cooking times for the soda cooks were significantly shorter than that for the kraft cook. The ODiMAQ catalyzed cooking time was much shorter than that of the AQ cook. It might be possible to replace the kraft...

The effect of tonal changes on voice onset time in Mandarin esophageal speech.

PubMed

Liu, Hanjun; Ng, Manwa L; Wan, Mingxi; Wang, Supin; Zhang, Yi

2008-03-01

The present study investigated the effect of tonal changes on voice onset time (VOT) between normal laryngeal (NL) and superior esophageal (SE) speakers of Mandarin Chinese. VOT values were measured from the syllables /pha/, /tha/, and /kha/ produced at four tone levels by eight NL and seven SE speakers who were native speakers of Mandarin. Results indicated that Mandarin tones were associated with significantly different VOT values for NL speakers, in which high-falling tone was associated with significantly shorter VOT values than mid-rising tone and falling-rising tone. Regarding speaker group, SE speakers showed significantly shorter VOT values than NL speakers across all tone levels. This may be related to their use of pharyngoesophageal (PE) segment as another sound source. SE speakers appear to take a shorter time to start PE segment vibration compared to NL speakers using the vocal folds for vibration.

How many hours do people sleep in Bangladesh? A country-representative survey.

PubMed

Yunus, Fakir M; Khan, Safayet; Akter, Tahera; Jhohura, Fatema T; Reja, Saifur; Islam, Akramul; Rahman, Mahfuzar

2016-06-01

This study investigated total sleep time in the Bangladeshi population and identified the proportion of the population at greater risk of developing chronic diseases due to inadequate sleep. Using a cross-sectional survey, total sleep time was captured and analysed in 3968 respondents aged between 6 and 106 years in 24 (of 64) districts in Bangladesh. Total sleep time was defined as the hours of total sleep in the previous 24 h. We used National Sleep Foundation (2015) guidelines to determine the recommended sleep hours in different age categories. Less or more than the recommended total sleep time (in hours) was considered 'shorter' and 'longer' sleep time, respectively. Linear and multinomial logistic regression models were used to determine the relationship between demographic variables and estimated risk of shorter and longer total sleep time. The mean (±standard deviation) total sleep time of children (6-13 years), teenagers (14-17 years), young adults and adults (18-64 years) and older adults (≥65 years) were 8.6 (±1.1), 8.1 (±1.0), 7.7 (±0.9) and 7.8 (±1.4) h, respectively, which were significantly different (P < 0.01). More than half of school-age children (55%) slept less than, and 28.2% of older adults slept longer than, recommended. Residents in all divisions (except Chittagong) in Bangladesh were less likely to sleep longer than in the Dhaka division. Rural populations had a 3.96× greater chance of sleeping for a shorter time than urban residents. The Bangladeshi population tends to sleep for longer and/or shorter times than their respective recommended sleep hours, which is detrimental to health. © 2016 European Sleep Research Society.

Computed tomographic pelvimetry in English bulldogs.

PubMed

Dobak, Tetyda P; Voorhout, George; Vernooij, Johannes C M; Boroffka, Susanne A E B

2018-05-31

English bulldogs have been reported to have a high incidence of dystocia and caesarean section is often performed electively in this breed. A narrow pelvic canal is the major maternal factor contributing to obstructive dystocia. The objective of this cross-sectional study was to assess the pelvic dimensions of 40 clinically healthy English bulldogs using computed tomography pelvimetry. A control group consisting of 30 non-brachycephalic dogs that underwent pelvic computed tomography was retrospectively collected from the patient archive system. Univariate analysis of variance was used to compare computed tomography pelvimetry of both groups and the effects of weight and gender on the measurements. In addition, ratios were obtained to address pelvic shape differences. A significantly (P = 0.00) smaller pelvic size was found in English bulldogs compared to the control group for all computed tomography measurements: width and length of the pelvis, pelvic inlet and caudal pelvic aperture. The pelvic conformation was significantly different between the groups, English bulldogs had an overall shorter pelvis and pelvic canal and a narrower pelvic outlet. Weight had a significant effect on all measurements whereas gender that only had a significant effect on some (4/11) pelvic dimensions. Our findings prove that English bulldogs have a generally reduced pelvic size as well as a shorter pelvis and narrower pelvic outlet when compared to non-brachycephalic breeds. We suggest that some of our measurements may serve as a baseline for pelvic dimensions in English bulldogs and may be useful for future studies on dystocia in this breed. Copyright © 2018 Elsevier Inc. All rights reserved.

zipHMMlib: a highly optimised HMM library exploiting repetitions in the input to speed up the forward algorithm.

PubMed

Sand, Andreas; Kristiansen, Martin; Pedersen, Christian N S; Mailund, Thomas

2013-11-22

Hidden Markov models are widely used for genome analysis as they combine ease of modelling with efficient analysis algorithms. Calculating the likelihood of a model using the forward algorithm has worst case time complexity linear in the length of the sequence and quadratic in the number of states in the model. For genome analysis, however, the length runs to millions or billions of observations, and when maximising the likelihood hundreds of evaluations are often needed. A time efficient forward algorithm is therefore a key ingredient in an efficient hidden Markov model library. We have built a software library for efficiently computing the likelihood of a hidden Markov model. The library exploits commonly occurring substrings in the input to reuse computations in the forward algorithm. In a pre-processing step our library identifies common substrings and builds a structure over the computations in the forward algorithm which can be reused. This analysis can be saved between uses of the library and is independent of concrete hidden Markov models so one preprocessing can be used to run a number of different models.Using this library, we achieve up to 78 times shorter wall-clock time for realistic whole-genome analyses with a real and reasonably complex hidden Markov model. In one particular case the analysis was performed in less than 8 minutes compared to 9.6 hours for the previously fastest library. We have implemented the preprocessing procedure and forward algorithm as a C++ library, zipHMM, with Python bindings for use in scripts. The library is available at http://birc.au.dk/software/ziphmm/.

Thermosphere Global Time Response to Geomagnetic Storms Caused by Coronal Mass Ejections

NASA Astrophysics Data System (ADS)

Oliveira, D. M.; Zesta, E.; Schuck, P. W.; Sutton, E. K.

2017-10-01

We investigate, for the first time with a spatial superposed epoch analysis study, the thermosphere global time response to 159 geomagnetic storms caused by coronal mass ejections (CMEs) observed in the solar wind at Earth's orbit during the period of September 2001 to September 2011. The thermosphere neutral mass density is obtained from the CHAMP (CHAllenge Mini-Satellite Payload) and GRACE (Gravity Recovery Climate Experiment) spacecraft. All density measurements are intercalibrated against densities computed by the Jacchia-Bowman 2008 empirical model under the regime of very low geomagnetic activity. We explore both the effects of the pre-CME shock impact on the thermosphere and of the storm main phase onset by taking their times of occurrence as zero epoch times (CME impact and interplanetary magnetic field Bz southward turning) for each storm. We find that the shock impact produces quick and transient responses at the two high-latitude regions with minimal propagation toward lower latitudes. In both cases, thermosphere is heated in very high latitude regions within several minutes. The Bz southward turning of the storm onset has a fast heating manifestation at the two high-latitude regions, and it takes approximately 3 h for that heating to propagate down to equatorial latitudes and to globalize in the thermosphere. This heating propagation is presumably accomplished, at least in part, with traveling atmospheric disturbances and complex meridional wind structures. Current models use longer lag times in computing thermosphere density dynamics during storms. Our results suggest that the thermosphere response time scales are shorter and should be accordingly adjusted in thermospheric empirical models.

Comparing Outcomes and Cost of 3 Surgical Treatments for Sagittal Synostosis: A Retrospective Study Including Procedure-Related Cost Analysis.

PubMed

Garber, Sarah T; Karsy, Michael; Kestle, John R W; Siddiqi, Faizi; Spanos, Stephen P; Riva-Cambrin, Jay

2017-10-01

Neurosurgical techniques for repair of sagittal synostosis include total cranial vault (TCV) reconstruction, open sagittal strip (OSS) craniectomy, and endoscopic strip (ES) craniectomy. To evaluate outcomes and cost associated with these 3 techniques. Via retrospective chart review with waiver of informed consent, the last consecutive 100 patients with sagittal synostosis who underwent each of the 3 surgical correction techniques before June 30, 2013, were identified. Clinical, operative, and process of care variables and their associated specific charges were analyzed along with overall charge. The study included 300 total patients. ES patients had fewer transfusion requirements (13% vs 83%, P < .001) than TCV patients, fewer days in intensive care (0.3 vs 1.3, P < .001), and a shorter overall hospital stay (1.8 vs 4.2 d, P < .001), and they required fewer revisions (1% vs 6%, P = .05). The mean charge for the endoscopic procedure was $21 203, whereas the mean charge for the TCV reconstruction was $45 078 (P < .001). ES patients had more preoperative computed tomography scans (66% vs 44%, P = .003) than OSS patients, shorter operative times (68 vs 111 min, P < .001), and required fewer revision procedures (1% vs 8%, P < .001). The mean charge for the endoscopic procedure was $21 203 vs $20 535 for the OSS procedure (P = .62). The ES craniectomy for sagittal synostosis appeared to have less morbidity and a potential cost savings compared with the TCV reconstruction. The charges were similar to those incurred with OSS craniectomy, but patients had a shorter length of stay and fewer revisions. Copyright © 2017 by the Congress of Neurological Surgeons

Introducing robotic surgery into an endometrial cancer service--a prospective evaluation of clinical and economic outcomes in a UK institution.

PubMed

Ind, Thomas E J; Marshall, Chris; Hacking, Matthew; Harris, Michelle; Bishop, Liz; Barton, Desmond; Bridges, Jane E; Shepherd, John H; Nobbenhuis, Marielle

2016-03-01

We have assessed how the introduction of robotics in a publicly funded endometrial cancer service affects clinical and economic outcomes. The study included 196 women. Costs were divided into those for wards, high dependency, staffing, theatres, pharmacy, blood products, imaging, pathology and rehabilitation. Capital depreciation was included. Prior to the introduction of robotics, 78/130 (60.0%) cases were performed open, compared to 17/66 (25.8%) afterwards (p < 0.0001). The median operative time increased 37 min (95% CI 17-55 min; p = 0.0002); the median blood loss was 55 ml lower (95% CI 0-150 ml; p = 0.0181); the stay was 2 days shorter (95% CI 1-3; p < 0.0001). Complications reduced from 64/130 (49.2%) to 19/66 (28.8%) (p = 0.0045). Costs reduced from £11 476 to £10 274 (p = 0.0065). Conversions for 'straight stick' surgery were 18.2% (14/77) compared to 0.0% (0/24) for robotics (p = 0.0164). Introducing robotics resulted in fewer laparotomies, shorter stays, fewer complications and lower costs. © 2015 The Authors. The International Journal of Medical Robotics and Computer Assisted Surgery Published by John Wiley & Sons Ltd.

Serum Iron Level Is Associated with Time to Antibiotics in Cystic Fibrosis.

PubMed

Gifford, Alex H; Dorman, Dana B; Moulton, Lisa A; Helm, Jennifer E; Griffin, Mary M; MacKenzie, Todd A

2015-12-01

Serum levels of hepcidin-25, a peptide hormone that reduces blood iron content, are elevated when patients with cystic fibrosis (CF) develop pulmonary exacerbation (PEx). Because hepcidin-25 is unavailable as a clinical laboratory test, we questioned whether a one-time serum iron level was associated with the subsequent number of days until PEx, as defined by the need to receive systemic antibiotics (ABX) for health deterioration. Clinical, biochemical, and microbiological parameters were simultaneously checked in 54 adults with CF. Charts were reviewed to determine when they first experienced a PEx after these parameters were assessed. Time to ABX was compared in subgroups with and without specific attributes. Multivariate linear regression was used to identify parameters that significantly explained variation in time to ABX. In univariate analyses, time to ABX was significantly shorter in subjects with Aspergillus-positive sputum cultures and CF-related diabetes. Multivariate linear regression models demonstrated that shorter time to ABX was associated with younger age, lower serum iron level, and Aspergillus sputum culture positivity. Serum iron, age, and Aspergillus sputum culture positivity are factors associated with shorter time to subsequent PEx in CF adults. © 2015 Wiley Periodicals, Inc.

Anesthetic efficacy of ketamine-diazepam, ketamine-xylazine, and ketamine-acepromazine in Caspian Pond turtles (Mauremys caspica).

PubMed

Adel, Milad; Sadegh, Amin Bigham; Arizza, Vincenzo; Abbasi, Hossein; Inguglia, Luigi; Saravi, Hasan Nasrollahzadeh

2017-01-01

The objective of this study was to assess the efficacy of different anesthetic drug combinations on the Caspian Pond turtles ( Mauremys caspica ). Three groups of the Caspian Pond turtles ( n = 6) were anesthetized with three different drug combinations. Initially, a pilot study was conducted to determine the best drug doses for the anesthetization of the turtles, and according to these results, ketamine-diazepam (120 mg/kg ketamine hydrochloride [5%] and 2 mg/kg diazepam [5%]), ketamine-acepromazine (120 mg/kg ketamine hydrochloride [5%] and 1 mg/kg acepromazine [1%]), and ketamine-xylazine (120 mg/kg ketamine hydrochloride [5%] and 1 mg/kg xylazine [2%]) were injected intramuscularly. The onset times of anesthetization and the recovery time were measured. Statistical analysis of the data was performed using one-way analysis of variance followed by t -tests, and P < 0.05 was considered statistically significant. There were statistically significant differences in the mean of the onset times of anesthesia and recovery time among the three drug combinations depending on the treatment used. The onset of anesthesia of the animals treated with the ketamine-diazepam combination was 60% and 42% shorter, for male and female turtles, respectively, compared to that obtained with the ketamine-acepromazine combination and 64% (male turtles) and 50% (female turtles) shorter than that obtained with the ketamine-xylazine combination. Further, the recovery time, in male turtles, was 17% shorter in animals treated with the first drug combination than those treated with the ketamine-acepromazine combination and 37% shorter than those treated with the ketamine-xylazine combination. The recovery time, in female turtles, did not seem to be significantly different among treatments. The study showed that the ketamine-diazepam drug combination is the anesthetic combination with the fastest onset time and shortest recovery time.

Facial palsy in children: emergency department management and outcome.

PubMed

Wang, Cheng-Hsien; Chang, Yu-Che; Shih, Hong-Mo; Chen, Chun-Yu; Chen, Jih-Chang

2010-02-01

To describe the characteristics of children who present to an emergency department (ED) with facial palsy and determine the association of outcome with etiology, degree of initial paralysis, and ED management. This was a retrospective cohort study of children who presented to an ED with facial nerve paralysis (FNP). There were 85 patients with a mean age of 8.0 (SD, 6.1) years; 60% (n = 51) of the patients were male, and 65.9% (n = 56) were admitted to the hospital. Bell palsy (50.6%) was the most common etiology followed by infectious (22.4%), traumatic (16.5%), congenital (7.1%), and neoplastic etiologies (3.5%). Patients with Bell palsy had shorter recovery times (P = 0.049), and traumatic cases required a longer time for recovery (P = 0.016). Acute otitis media (AOM)-related pediatric FNP had shorter recovery times than non-AOM-related cases (P = 0.005) in infectious group. Patients given steroid therapy did not have a shorter recovery time (P = 0.237) or a better recovery (P = 0.269). There was no difference in recovery rate of pediatric patients with Bell palsy between hospitalization or not (P = 0.952). Bell palsy, infection, and trauma were most common etiologies of pediatric FNP. Recovery times were shorter in pediatric patients with Bell palsy and AOM-related FNP, whereas recovery took longer in traumatic cases. Steroid therapy did not seem beneficial for pediatric FNP. Hospitalization is not indicated for pediatric patients with Bell palsy.

Variable-Field Analytical Ultracentrifugation: I. Time-Optimized Sedimentation Equilibrium

PubMed Central

Ma, Jia; Metrick, Michael; Ghirlando, Rodolfo; Zhao, Huaying; Schuck, Peter

2015-01-01

Sedimentation equilibrium (SE) analytical ultracentrifugation (AUC) is a gold standard for the rigorous determination of macromolecular buoyant molar masses and the thermodynamic study of reversible interactions in solution. A significant experimental drawback is the long time required to attain SE, which is usually on the order of days. We have developed a method for time-optimized SE (toSE) with defined time-varying centrifugal fields that allow SE to be attained in a significantly (up to 10-fold) shorter time than is usually required. To achieve this, numerical Lamm equation solutions for sedimentation in time-varying fields are computed based on initial estimates of macromolecular transport properties. A parameterized rotor-speed schedule is optimized with the goal of achieving a minimal time to equilibrium while limiting transient sample preconcentration at the base of the solution column. The resulting rotor-speed schedule may include multiple over- and underspeeding phases, balancing the formation of gradients from strong sedimentation fluxes with periods of high diffusional transport. The computation is carried out in a new software program called TOSE, which also facilitates convenient experimental implementation. Further, we extend AUC data analysis to sedimentation processes in such time-varying centrifugal fields. Due to the initially high centrifugal fields in toSE and the resulting strong migration, it is possible to extract sedimentation coefficient distributions from the early data. This can provide better estimates of the size of macromolecular complexes and report on sample homogeneity early on, which may be used to further refine the prediction of the rotor-speed schedule. In this manner, the toSE experiment can be adapted in real time to the system under study, maximizing both the information content and the time efficiency of SE experiments. PMID:26287634

Short time ahead wind power production forecast

NASA Astrophysics Data System (ADS)

Sapronova, Alla; Meissner, Catherine; Mana, Matteo

2016-09-01

An accurate prediction of wind power output is crucial for efficient coordination of cooperative energy production from different sources. Long-time ahead prediction (from 6 to 24 hours) of wind power for onshore parks can be achieved by using a coupled model that would bridge the mesoscale weather prediction data and computational fluid dynamics. When a forecast for shorter time horizon (less than one hour ahead) is anticipated, an accuracy of a predictive model that utilizes hourly weather data is decreasing. That is because the higher frequency fluctuations of the wind speed are lost when data is averaged over an hour. Since the wind speed can vary up to 50% in magnitude over a period of 5 minutes, the higher frequency variations of wind speed and direction have to be taken into account for an accurate short-term ahead energy production forecast. In this work a new model for wind power production forecast 5- to 30-minutes ahead is presented. The model is based on machine learning techniques and categorization approach and using the historical park production time series and hourly numerical weather forecast.

Microcomputer Network for Computerized Adaptive Testing (CAT). [Final Report, FY81-83].

ERIC Educational Resources Information Center

Quan, Baldwin; And Others

Computerized adaptive testing (CAT) offers the opportunity to replace paper-and-pencil aptitude tests such as the Armed Services Vocational Aptitude Battery with shorter, more accurate, and more secure computer-administered tests. Its potential advantages need to be verified by experimental administration of automated tests to military recruit…

Design of a short nonuniform acquisition protocol for quantitative analysis in dynamic cardiac SPECT imaging - a retrospective 123 I-MIBG animal study.

PubMed

Zan, Yunlong; Long, Yong; Chen, Kewei; Li, Biao; Huang, Qiu; Gullberg, Grant T

2017-07-01

Our previous works have found that quantitative analysis of 123 I-MIBG kinetics in the rat heart with dynamic single-photon emission computed tomography (SPECT) offers the potential to quantify the innervation integrity at an early stage of left ventricular hypertrophy. However, conventional protocols involving a long acquisition time for dynamic imaging reduce the animal survival rate and thus make longitudinal analysis difficult. The goal of this work was to develop a procedure to reduce the total acquisition time by selecting nonuniform acquisition times for projection views while maintaining the accuracy and precision of estimated physiologic parameters. Taking dynamic cardiac imaging with 123 I-MIBG in rats as an example, we generated time activity curves (TACs) of regions of interest (ROIs) as ground truths based on a direct four-dimensional reconstruction of experimental data acquired from a rotating SPECT camera, where TACs represented as the coefficients of B-spline basis functions were used to estimate compartmental model parameters. By iteratively adjusting the knots (i.e., control points) of B-spline basis functions, new TACs were created according to two rules: accuracy and precision. The accuracy criterion allocates the knots to achieve low relative entropy between the estimated left ventricular blood pool TAC and its ground truth so that the estimated input function approximates its real value and thus the procedure yields an accurate estimate of model parameters. The precision criterion, via the D-optimal method, forces the estimated parameters to be as precise as possible, with minimum variances. Based on the final knots obtained, a new protocol of 30 min was built with a shorter acquisition time that maintained a 5% error in estimating rate constants of the compartment model. This was evaluated through digital simulations. The simulation results showed that our method was able to reduce the acquisition time from 100 to 30 min for the cardiac study of rats with 123 I-MIBG. Compared to a uniform interval dynamic SPECT protocol (1 s acquisition interval, 30 min acquisition time), the newly proposed protocol with nonuniform interval achieved comparable (K1 and k2, P = 0.5745 for K1 and P = 0.0604 for k2) or better (Distribution Volume, DV, P = 0.0004) performance for parameter estimates with less storage and shorter computational time. In this study, a procedure was devised to shorten the acquisition time while maintaining the accuracy and precision of estimated physiologic parameters in dynamic SPECT imaging. The procedure was designed for 123 I-MIBG cardiac imaging in rat studies; however, it has the potential to be extended to other applications, including patient studies involving the acquisition of dynamic SPECT data. © 2017 American Association of Physicists in Medicine.

Comparison of Er:YAG laser and surgical drill for osteotomy in oral surgery: an experimental study.

PubMed

Gabrić Pandurić, Dragana; Bago, Ivona; Katanec, Davor; Zabkar, Janez; Miletić, Ivana; Anić, Ivica

2012-11-01

High-energy lasers have been proposed as an alternative to the conventional surgical drill in oral and maxillofacial surgery. The aims of this study were to compare thermal changes of the bone surface, procedure time, and volume of the removed bone after drilling with an erbium (Er):yttrium-aluminum-garnet (YAG) laser versus a low-speed surgical drill. The bone sections were observed under light microscopy and examined histologically. Thirty bone blocks were prepared from porcine ribs. On each block 2 holes (tunnel preparations) were performed using a low-speed, 1.0-mm-wide, surgical pilot drill and an Er:YAG laser (pulse energy, 1,000 mJ; pulse duration, 300 μs; frequency, 20 Hz). The temperature induced by the preparation techniques was measured using an infrared camera. The removed bone volume was calculated by a modified mathematical algorithm. The time required for the preparation was measured with a digital stopwatch and a time-measurement instrument integrated within the computer program. The cortical and spongiose surfaces of the specimens were examined microscopically and histologically under a light microscope with a high-resolution camera. The Er:YAG laser removed significantly more bone tissue than the drill (P < .01) in a significantly shorter time (P < .01). The temperature was statistically lower during the laser preparation (P < .01). Cavities prepared with the laser were regular with clear sharp edges and knifelike cuts. In the drill group, the preparations exhibited irregular edges full of bone fragments and fiberlike debris. Histologic examination of the laser sides showed a 30-μm-thick altered sublayer. The tissue in the drill group was covered with a smear layer without any alterations. The Er:YAG laser produced preparations with regular and sharp edges, without bone fragments and debris, in a shorter time, and with less generated heat. Thermal alterations in the treated surface were minimal. Copyright © 2012 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

An extended validation of the last generation of particle finite element method for free surface flows

NASA Astrophysics Data System (ADS)

Gimenez, Juan M.; González, Leo M.

2015-03-01

In this paper, a new generation of the particle method known as Particle Finite Element Method (PFEM), which combines convective particle movement and a fixed mesh resolution, is applied to free surface flows. This interesting variant, previously described in the literature as PFEM-2, is able to use larger time steps when compared to other similar numerical tools which implies shorter computational times while maintaining the accuracy of the computation. PFEM-2 has already been extended to free surface problems, being the main topic of this paper a deep validation of this methodology for a wider range of flows. To accomplish this task, different improved versions of discontinuous and continuous enriched basis functions for the pressure field have been developed to capture the free surface dynamics without artificial diffusion or undesired numerical effects when different density ratios are involved. A collection of problems has been carefully selected such that a wide variety of Froude numbers, density ratios and dominant dissipative cases are reported with the intention of presenting a general methodology, not restricted to a particular range of parameters, and capable of using large time-steps. The results of the different free-surface problems solved, which include: Rayleigh-Taylor instability, sloshing problems, viscous standing waves and the dam break problem, are compared to well validated numerical alternatives or experimental measurements obtaining accurate approximations for such complex flows.

Speckle-field propagation in 'frozen' turbulence: brightness function approach

NASA Astrophysics Data System (ADS)

Dudorov, Vadim V.; Vorontsov, Mikhail A.; Kolosov, Valeriy V.

2006-08-01

Speckle-field long- and short-exposure spatial correlation characteristics for target-in-the-loop (TIL) laser beam propagation and scattering in atmospheric turbulence are analyzed through the use of two different approaches: the conventional Monte Carlo (MC) technique and the recently developed brightness function (BF) method. Both the MC and the BF methods are applied to analysis of speckle-field characteristics averaged over target surface roughness realizations under conditions of 'frozen' turbulence. This corresponds to TIL applications where speckle-field fluctuations associated with target surface roughness realization updates occur within a time scale that can be significantly shorter than the characteristic atmospheric turbulence time. Computational efficiency and accuracy of both methods are compared on the basis of a known analytical solution for the long-exposure mutual correlation function. It is shown that in the TIL propagation scenarios considered the BF method provides improved accuracy and requires significantly less computational time than the conventional MC technique. For TIL geometry with a Gaussian outgoing beam and Lambertian target surface, both analytical and numerical estimations for the speckle-field long-exposure correlation length are obtained. Short-exposure speckle-field correlation characteristics corresponding to propagation in 'frozen' turbulence are estimated using the BF method. It is shown that atmospheric turbulence-induced static refractive index inhomogeneities do not significantly affect the characteristic correlation length of the speckle field, whereas long-exposure spatial correlation characteristics are strongly dependent on turbulence strength.

Speckle-field propagation in 'frozen' turbulence: brightness function approach.

PubMed

Dudorov, Vadim V; Vorontsov, Mikhail A; Kolosov, Valeriy V

2006-08-01

Speckle-field long- and short-exposure spatial correlation characteristics for target-in-the-loop (TIL) laser beam propagation and scattering in atmospheric turbulence are analyzed through the use of two different approaches: the conventional Monte Carlo (MC) technique and the recently developed brightness function (BF) method. Both the MC and the BF methods are applied to analysis of speckle-field characteristics averaged over target surface roughness realizations under conditions of 'frozen' turbulence. This corresponds to TIL applications where speckle-field fluctuations associated with target surface roughness realization updates occur within a time scale that can be significantly shorter than the characteristic atmospheric turbulence time. Computational efficiency and accuracy of both methods are compared on the basis of a known analytical solution for the long-exposure mutual correlation function. It is shown that in the TIL propagation scenarios considered the BF method provides improved accuracy and requires significantly less computational time than the conventional MC technique. For TIL geometry with a Gaussian outgoing beam and Lambertian target surface, both analytical and numerical estimations for the speckle-field long-exposure correlation length are obtained. Short-exposure speckle-field correlation characteristics corresponding to propagation in 'frozen' turbulence are estimated using the BF method. It is shown that atmospheric turbulence-induced static refractive index inhomogeneities do not significantly affect the characteristic correlation length of the speckle field, whereas long-exposure spatial correlation characteristics are strongly dependent on turbulence strength.

Nonuniform update for sparse target recovery in fluorescence molecular tomography accelerated by ordered subsets.

PubMed

Zhu, Dianwen; Li, Changqing

2014-12-01

Fluorescence molecular tomography (FMT) is a promising imaging modality and has been actively studied in the past two decades since it can locate the specific tumor position three-dimensionally in small animals. However, it remains a challenging task to obtain fast, robust and accurate reconstruction of fluorescent probe distribution in small animals due to the large computational burden, the noisy measurement and the ill-posed nature of the inverse problem. In this paper we propose a nonuniform preconditioning method in combination with L (1) regularization and ordered subsets technique (NUMOS) to take care of the different updating needs at different pixels, to enhance sparsity and suppress noise, and to further boost convergence of approximate solutions for fluorescence molecular tomography. Using both simulated data and phantom experiment, we found that the proposed nonuniform updating method outperforms its popular uniform counterpart by obtaining a more localized, less noisy, more accurate image. The computational cost was greatly reduced as well. The ordered subset (OS) technique provided additional 5 times and 3 times speed enhancements for simulation and phantom experiments, respectively, without degrading image qualities. When compared with the popular L (1) algorithms such as iterative soft-thresholding algorithm (ISTA) and Fast iterative soft-thresholding algorithm (FISTA) algorithms, NUMOS also outperforms them by obtaining a better image in much shorter period of time.

Outcome after introduction of laparoscopic appendectomy in children: A cohort study.

PubMed

Svensson, Jan F; Patkova, Barbora; Almström, Markus; Eaton, Simon; Wester, Tomas

2016-03-01

Acute appendicitis in children is common and the optimal treatment modality is still debated, even if recent data suggest that laparoscopic surgery may result in shorter postoperative length of stay without an increased number of complications. The aim of the study was to compare the outcome of open and laparoscopic appendectomies during a transition period. This was a retrospective cohort study with prospectively collected data. All patients who underwent an operation for suspected appendicitis at the Astrid Lindgren Children's Hospital in Stockholm between 2006 and 2010 were included in the study. 1745 children were included in this study, of whom 1010 had a laparoscopic intervention. There were no significant differences in the rate of postoperative abscesses, wound infections, readmissions or reoperations between the two groups. The median operating time was longer for laparoscopic appendectomy than for open appendectomy, 51 vs. 37minutes (p<0.05). The postoperative length of stay was similar in the two groups. A simple comparison between the groups suggested that laparoscopic appendectomy had a shorter median postoperative length of stay, 43 vs. 57hours (p<0.05). However, there was a trend in time for a shorter postoperative length of stay, and a trend for more of the procedures to be performed laparoscopically over time so on regression analysis, the apparent decrease in length of stay with laparoscopy could be ascribed to the general trend toward decreased length of stay over time, with no specific additional effect of laparoscopy. Our data show no difference in outcome between open and laparoscopic surgery for acute appendicitis in children in regard of complications. The initial assumption that the patients treated with laparoscopic surgery had a shorter postoperative stay was not confirmed with linear regression, which showed that the assumed difference was due only to a trend toward shorter postoperative length of stay over time, regardless of the surgical intervention. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Media devices, family relationships and sleep patterns among adolescents in an urban area.

PubMed

Continente, Xavier; Pérez, Anna; Espelt, Albert; López, Maria José

2017-04-01

This study aimed to describe sleep patterns and to examine the association between short sleep time and family relationships and the availability of media devices among adolescents. A cross-sectional study based on a self-reported questionnaire was performed among a representative sample of adolescents (13-19 years old) enrolled during the 2011-2012 academic year in high schools in Barcelona, Spain. Adolescents reported sleep patterns and family-related variables such as family relationships, the availability of media devices in the bedroom, and watching television at dinner. Sleep time was then calculated from sleep patterns. Multivariate Poisson regression analyses with robust variance were conducted to determine the association between short sleep time (<8 h/day) and family characteristics. A total of 51.3% of the 3492 students were girls (mean age: 15.9 years). Sleep time was shorter than recommended on school days in almost half of the compulsory schooling students and in around 75% of post-compulsory schooling students. More than 80% of adolescents had at least one media device (television, console, or computer) in their bedroom. Adolescents with a computer in their bedroom and with poorer family relationships were more likely to be short sleepers. In boys, frequently watching TV at dinner and living in a disorganized family were also associated with short sleep time. There is a high prevalence of short sleepers. Media availability, media use and family relationships should be considered in multi-component educational interventions addressed to both adolescents and parents to reduce short sleep time. Copyright © 2016 Elsevier B.V. All rights reserved.

Simultaneous image reproduction on CRT screen: Moves ultrasonic sectional view and electrocardiogram curves

NASA Technical Reports Server (NTRS)

1978-01-01

A method for simultaneous reproduction of images, requiring different amounts of time to reproduce, on a cathode ray tube (CRT) screen is disclosed. Ultrasonic sectional views and electrocardiogram curves are simultaneously reproduced on the CRT screen by producing the images on different areas of a screen with two phosphors having different persistence times and luminous colors, within the times required for the appearance of the images. In front of the area on which is produced the image requiring the shorter time is a color filter which is permeable to the color of the phosphor with the shorter persistence time by which absorbs the color of the other phosphor.

Discharge-measurement system using an acoustic Doppler current profiler with applications to large rivers and estuaries

USGS Publications Warehouse

Simpson, Michael R.; Oltmann, Richard N.

1993-01-01

Discharge measurement of large rivers and estuaries is difficult, time consuming, and sometimes dangerous. Frequently, discharge measurements cannot be made in tide-affected rivers and estuaries using conventional discharge-measurement techniques because of dynamic discharge conditions. The acoustic Doppler discharge-measurement system (ADDMS) was developed by the U.S. Geological Survey using a vessel-mounted acoustic Doppler current profiler coupled with specialized computer software to measure horizontal water velocity at 1-meter vertical intervals in the water column. The system computes discharge from water-and vessel-velocity data supplied by the ADDMS using vector-algebra algorithms included in the discharge-measurement software. With this system, a discharge measurement can be obtained by engaging the computer software and traversing a river or estuary from bank to bank; discharge in parts of the river or estuarine cross sections that cannot be measured because of ADDMS depth limitations are estimated by the system. Comparisons of ADDMS-measured discharges with ultrasonic-velocity-meter-measured discharges, along with error-analysis data, have confirmed that discharges provided by the ADDMS are at least as accurate as those produced using conventional methods. In addition, the advantage of a much shorter measurement time (2 minutes using the ADDMS compared with 1 hour or longer using conventional methods) has enabled use of the ADDMS for several applications where conventional discharge methods could not have been used with the required accuracy because of dynamic discharge conditions.

Spot Sign in Acute Intracerebral Hemorrhage in Dynamic T1-Weighted Magnetic Resonance Imaging.

PubMed

Schindlbeck, Katharina A; Santaella, Anna; Galinovic, Ivana; Krause, Thomas; Rocco, Andrea; Nolte, Christian H; Villringer, Kersten; Fiebach, Jochen B

2016-02-01

In computed tomographic imaging of acute intracerebral hemorrhage spot sign on computed tomographic angiography has been established as a marker for hematoma expansion and poor clinical outcome. Although, magnetic resonance imaging (MRI) can accurately visualize acute intracerebral hemorrhage, a corresponding MRI marker is lacking to date. We prospectively examined 50 consecutive patients with acute intracerebral hemorrhage within 24 hours of symptom onset. The MRI protocol consisted of a standard stroke protocol and dynamic contrast-enhanced T1-weighted imaging with a time resolution of 7.07 s/batch. Stroke scores were assessed at admission and at time of discharge. Volume measurements of hematoma size and spot sign were performed with MRIcron. Contrast extravasation within sites of the hemorrhage (MRI spot sign) was seen in 46% of the patients. Patients with an MRI spot sign had a significantly shorter time to imaging than those without (P<0.001). The clinical outcome measured by the modified Rankin Scale was significantly worse in patients with spot sign compared with those without (P≤0.001). Hematoma expansion was observed in the spot sign group compared with the nonspot sign group, although the differences were not significant. Spot sign can be detected using MRI on postcontrast T1-weighted and dynamic T1-weighted images. It is associated with worse clinical outcome. The time course of contrast extravasation in dynamic T1 images indicates that these spots represent ongoing bleeding. © 2015 American Heart Association, Inc.

An efficient repeating signal detector to investigate earthquake swarms

NASA Astrophysics Data System (ADS)

Skoumal, Robert J.; Brudzinski, Michael R.; Currie, Brian S.

2016-08-01

Repetitive earthquake swarms have been recognized as key signatures in fluid injection induced seismicity, precursors to volcanic eruptions, and slow slip events preceding megathrust earthquakes. We investigate earthquake swarms by developing a Repeating Signal Detector (RSD), a computationally efficient algorithm utilizing agglomerative clustering to identify similar waveforms buried in years of seismic recordings using a single seismometer. Instead of relying on existing earthquake catalogs of larger earthquakes, RSD identifies characteristic repetitive waveforms by rapidly identifying signals of interest above a low signal-to-noise ratio and then grouping based on spectral and time domain characteristics, resulting in dramatically shorter processing time than more exhaustive autocorrelation approaches. We investigate seismicity in four regions using RSD: (1) volcanic seismicity at Mammoth Mountain, California, (2) subduction-related seismicity in Oaxaca, Mexico, (3) induced seismicity in Central Alberta, Canada, and (4) induced seismicity in Harrison County, Ohio. In each case, RSD detects a similar or larger number of earthquakes than existing catalogs created using more time intensive methods. In Harrison County, RSD identifies 18 seismic sequences that correlate temporally and spatially to separate hydraulic fracturing operations, 15 of which were previously unreported. RSD utilizes a single seismometer for earthquake detection which enables seismicity to be quickly identified in poorly instrumented regions at the expense of relying on another method to locate the new detections. Due to the smaller computation overhead and success at distances up to ~50 km, RSD is well suited for real-time detection of low-magnitude earthquake swarms with permanent regional networks.

A modified adaptive algorithm of dealing with the high chirp when chirped pulses propagating in optical fiber

NASA Astrophysics Data System (ADS)

Wu, Lianglong; Fu, Xiquan; Guo, Xing

2013-03-01

In this paper, we propose a modified adaptive algorithm (MAA) of dealing with the high chirp to efficiently simulate the propagation of chirped pulses along an optical fiber for the propagation distance shorter than the "temporal focal length". The basis of the MAA is that the chirp term of initial pulse is treated as the rapidly varying part by means of the idea of the slowly varying envelope approximation (SVEA). Numerical simulations show that the performance of the MAA is validated, and that the proposed method can decrease the number of sampling points by orders of magnitude. In addition, the computational efficiency of the MAA compared with the time-domain beam propagation method (BPM) can be enhanced with the increase of the chirp of initial pulse.

Faculty and Student Expectations and Perceptions of E-mail Communication in a Campus and Distance Doctor of Pharmacy Program

PubMed Central

Turner, Paul D.; Monaghan, Michael S.; Walters, Ryan W.; Merkel, Jennifer J.; Lipschultz, Jeremy H.; Lenz, Thomas L.

2010-01-01

Objective To examine faculty members' and students' expectations and perceptions of e-mail communication in a dual pathway pharmacy program. Methods Three parallel survey instruments were administered to campus students, distance students, and faculty members, respectively. Focus groups with students and faculty were conducted. Results Faculty members perceived themselves as more accessible and approachable by e-mail than either group of students did. Campus students expected a shorter faculty response time to e-mail and for faculty members to be more available than did distance students. Conclusion E-mail is an effective means of computer-mediated communication between faculty members and students and can be used to promote a sense of community and inclusiveness (ie, immediacy), especially with distant students. PMID:21436932

Electronic media use and sleep in school-aged children and adolescents: A review.

PubMed

Cain, Neralie; Gradisar, Michael

2010-09-01

Electronic media have often been considered to have a negative impact on the sleep of children and adolescents, but there are no comprehensive reviews of research in this area. The present study identified 36 papers that have investigated the relationship between sleep and electronic media in school-aged children and adolescents, including television viewing, use of computers, electronic gaming, and/or the internet, mobile telephones, and music. Many variables have been investigated across these studies, although delayed bedtime and shorter total sleep time have been found to be most consistently related to media use. A model of the mechanisms by which media use may affect sleep is presented and discussed as a vehicle for future research. Copyright 2010 Elsevier B.V. All rights reserved.

Anesthetic drugs and onset of malignant hyperthermia.

PubMed

Visoiu, Mihaela; Young, Michael C; Wieland, Keith; Brandom, Barbara W

2014-02-01

The time between the beginning of anesthetic administration and recognition of the first sign of malignant hyperthermia (MH) (MH onset time) could differ among anesthetic drugs. We examined the time of the first signs of suspected MH, anesthetic drugs administered, subject age, and year of event in Adverse Metabolic/Musculoskeletal Reaction to Anesthesia reports in the North American Malignant Hyperthermia Registry. Inclusion criteria were judgment by the reporting clinician that the event was possible or fulminant MH, documentation of the time when anesthetic administration began, and the time when the first MH sign was noted. Descriptive statistics, Kruskal-Wallis analysis, and nonparametric correlation were used to assess the difference in MH onset times under different conditions. Four hundred seventy-seven cases met inclusion criteria; 58.5% were possible MH and 41.5% fulminant MH. Inhaled anesthetic and succinylcholine were given in 53.9% of cases, inhaled anesthetic only in 41.7%, and succinylcholine without inhaled anesthetics in 2.9%. No causative anesthetic drugs were reported in 7 MH cases. In 394 patients exposed to only 1 of the 4 inhaled anesthetics, without regard for subject age, MH onset time was shorter in the presence of halothane than any of the other anesthetics and shorter after succinylcholine in all anesthetics. If succinylcholine was not given, MH onset was shorter during sevoflurane anesthesia than during desflurane or isoflurane. In 322 cases, 1 rather than multiple first signs of MH were reported with masseter spasm as the earliest MH sign. In 339 cases in which masseter spasm was not reported, there was no difference in MH onset time with or without succinylcholine. In 146 cases in which masseter spasm was not reported and succinylcholine was not given, MH onset was shorter during halothane anesthesia, than during exposure to desflurane, or isoflurane. MH onset time during sevoflurane was shorter than during desflurane or isoflurane. MH was reported later in the course of anesthesia after 1998, when halothane and succinylcholine were less often reported. MH occurred after succinylcholine administration in the absence of inhaled anesthetics. We could not separate an effect of age from that of other variables. The onset of MH has been observed later during desflurane and isoflurane anesthesia than during exposure to sevoflurane. Since 1998, MH signs have more often appeared later, in the second or third hour of anesthesia, than they did before 1998.

Call-to-balloon time dashboard in patients with ST-segment elevation myocardial infarction results in significant improvement in the logistic chain.

PubMed

Hermans, Maaike P J; Velders, Matthijs A; Smeekes, Martin; Drexhage, Olivier S; Hautvast, Raymond W M; Ytsma, Timon; Schalij, Martin J; Umans, Victor A W M

2017-08-04

Timely reperfusion with primary percutaneous coronary intervention (pPCI) in ST-segment elevation myocardial infarction (STEMI) patients is associated with superior clinical outcomes. Aiming to reduce ischaemic time, an innovative system for home-to-hospital (H2H) time monitoring was implemented, which enabled real-time evaluation of ischaemic time intervals, regular feedback and improvements in the logistic chain. The objective of this study was to assess the results after implementation of the H2H dashboard for monitoring and evaluation of ischaemic time in STEMI patients. Ischaemic time in STEMI patients transported by emergency medical services (EMS) and treated with pPCI in the Noordwest Ziekenhuis, Alkmaar before (2008-2009; n=495) and after the implementation of the H2H dashboard (2011-2014; n=441) was compared. Median time intervals were significantly shorter in the H2H group (door-to-balloon time 32 [IQR 25-43] vs. 40 [IQR 28-55] minutes, p-value <0.001, FMC-to-balloon time 62 [IQR 52-75] vs. 80 [IQR 67-103] minutes, p-value <0.001, and treatment delay 142 [IQR 103-221] vs. 159 [IQR 123-253] minutes, p-value <0.001). The H2H time dashboard was independently associated with shorter time delays. Real-time monitoring and feedback on time delay with the H2H dashboard improves the logistic chain in STEMI patients, resulting in shorter ischaemic time intervals.

A Virtual Reality System for PTCD Simulation Using Direct Visuo-Haptic Rendering of Partially Segmented Image Data.

PubMed

Fortmeier, Dirk; Mastmeyer, Andre; Schröder, Julian; Handels, Heinz

2016-01-01

This study presents a new visuo-haptic virtual reality (VR) training and planning system for percutaneous transhepatic cholangio-drainage (PTCD) based on partially segmented virtual patient models. We only use partially segmented image data instead of a full segmentation and circumvent the necessity of surface or volume mesh models. Haptic interaction with the virtual patient during virtual palpation, ultrasound probing and needle insertion is provided. Furthermore, the VR simulator includes X-ray and ultrasound simulation for image-guided training. The visualization techniques are GPU-accelerated by implementation in Cuda and include real-time volume deformations computed on the grid of the image data. Computation on the image grid enables straightforward integration of the deformed image data into the visualization components. To provide shorter rendering times, the performance of the volume deformation algorithm is improved by a multigrid approach. To evaluate the VR training system, a user evaluation has been performed and deformation algorithms are analyzed in terms of convergence speed with respect to a fully converged solution. The user evaluation shows positive results with increased user confidence after a training session. It is shown that using partially segmented patient data and direct volume rendering is suitable for the simulation of needle insertion procedures such as PTCD.

Micro-computed tomographic comparison of nickel-titanium rotary versus traditional instruments in C-shaped root canal system.

PubMed

Yin, Xingzhe; Cheung, Gary Shun-Pan; Zhang, Chengfei; Masuda, Yoshiko Murakami; Kimura, Yuichi; Matsumoto, Koukichi

2010-04-01

The purpose of this study was to assess the efficacy of instrumentation of C-shaped canals with ProTaper rotary system and traditional instruments by using micro-computed tomography (micro-CT). Twenty-four mandibular molars with C-shaped canals were selected in pairs and sorted equally into 2 groups, which were assigned for instrumentation by ProTaper rotary system (ProTaper group) or by K-files and Gates-Glidden burs (Hand Instrument group). Three-dimensional images were constructed by micro-CT. The volume of dentin removed, uninstrumented canal area, time taken for instrumentation, and iatrogenic error of instrumentation were investigated. Hand Instrument group showed greater amount of volumetric dentin removal and left less uninstrumented canal area than ProTaper group (P < .01). The time needed for instrumentation was shorter for ProTaper group than for Hand Instrument group (P < .05). No instrument breakage occurred in both groups, but more conspicuous procedural errors were detected in Hand Instrument group than for ProTaper group. It was concluded that ProTaper rotary system maintained the canal curvature with speediness and few procedural errors, whereas traditional instrumentation can clean more canal surface. Copyright (c) 2010 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Compartmentalized self-replication under fast PCR cycling conditions yields Taq DNA polymerase mutants with increased DNA-binding affinity and blood resistance.

PubMed

Arezi, Bahram; McKinney, Nancy; Hansen, Connie; Cayouette, Michelle; Fox, Jeffrey; Chen, Keith; Lapira, Jennifer; Hamilton, Sarah; Hogrefe, Holly

2014-01-01

Faster-cycling PCR formulations, protocols, and instruments have been developed to address the need for increased throughput and shorter turn-around times for PCR-based assays. Although run times can be cut by up to 50%, shorter cycle times have been correlated with lower detection sensitivity and increased variability. To address these concerns, we applied Compartmentalized Self Replication (CSR) to evolve faster-cycling mutants of Taq DNA polymerase. After five rounds of selection using progressively shorter PCR extension times, individual mutations identified in the fastest-cycling clones were randomly combined using ligation-based multi-site mutagenesis. The best-performing combinatorial mutants exhibit 35- to 90-fold higher affinity (lower Kd ) for primed template and a moderate (2-fold) increase in extension rate compared to wild-type Taq. Further characterization revealed that CSR-selected mutations provide increased resistance to inhibitors, and most notably, enable direct amplification from up to 65% whole blood. We discuss the contribution of individual mutations to fast-cycling and blood-resistant phenotypes.

Is da Vinci Xi Better than da Vinci Si in Robotic Rectal Cancer Surgery? Comparison of the 2 Generations of da Vinci Systems.

PubMed

Ozben, Volkan; Cengiz, Turgut B; Atasoy, Deniz; Bayraktar, Onur; Aghayeva, Afag; Erguner, Ilknur; Baca, Bilgi; Hamzaoglu, Ismail; Karahasanoglu, Tayfun

2016-10-01

We aimed to compare perioperative outcomes for procedures using the latest generation of da Vinci robot versus its previous version in rectal cancer surgery. Fifty-three patients undergoing robotic rectal cancer surgery between January 2010 and March 2015 were included. Patients were classified into 2 groups (Xi, n=28 vs. Si, n=25) and perioperative outcomes were analyzed. The groups had significant differences including operative procedure, hybrid technique and redocking (P>0.05). In univariate analysis, the Xi group had shorter console times (265.7 vs. 317.1 min, P=0.006) and total operative times (321.6 vs. 360.4 min, P=0.04) and higher number of lymph nodes harvested (27.5 vs. 17.0, P=0.008). In multivariate analysis, Xi robot was associated with a shorter console time (odds ratio: 0.09, P=0.004) with no significant differences regarding other outcomes. Both generations of da Vinci robot led to similar short-term outcomes in rectal cancer surgery, but the Xi robot allowed shorter console times.

Description of the life stages of quill mite Mironovia lagopus sp. nov. (Acari: Syringophilidae) parasitizing the rock ptarmigan Lagopus muta (Phasianidae) from Iceland.

PubMed

Bochkov, Andre V; Skirnisson, Karl

2011-03-01

A new species of syringophilid mites, Mironovia lagopus sp. nov. (Acari: Syringophilidae) is described from feather quills of the rock ptarigman Lagopus muta (Montin) (Phasianidae) from Iceland. Females of this new species differ from the closely related Mironovia rouloul Skoracki and Sikora by setae d2, which are subequal or 1.1-1.2 times shorter than setae e2 (vs. d2 1.4-1.5 times longer than e2 in Mironovia rouloul) and by setae ag1, which are 1.3-1.5 times shorter than ag2 (vs. ag1 1.7-1.8 times shorter than ag2). The postembryonic stages of this new species are figured and described in details. In ontogeny of Mironovia spp., the observed pattern of setal appearance is not different from the pattern in other galliform-associated genera such as Syringophilus and Colinophilus, with exception for tarsal setae p'I, II which are absent in protonymphs. The key to all four species of the genus Mironovia is also provided.

Splint sterilization--a potential registration hazard in computer-assisted surgery.

PubMed

Figl, Michael; Weber, Christoph; Assadian, Ojan; Toma, Cyril D; Traxler, Hannes; Seemann, Rudolf; Guevara-Rojas, Godoberto; Pöschl, Wolfgang P; Ewers, Rolf; Schicho, Kurt

2012-04-01

Registration of preoperative targeting information for the intraoperative situation is a crucial step in computer-assisted surgical interventions. Point-to-point registration using acrylic splints is among the most frequently used procedures. There are, however, no generally accepted recommendations for sterilization of the splint. An appropriate method for the thermolabile splint would be hydrogen peroxide-based plasma sterilization. This study evaluated the potential deformation of the splint undergoing such sterilization. Deformation was quantified using image-processing methods applied to computed tomographic (CT) volumes before and after sterilization. An acrylic navigation splint was used as the study object. Eight metallic markers placed in the splint were used for registration. Six steel spheres in the mouthpiece were used as targets. Two CT volumes of the splint were acquired before and after 5 sterilization cycles using a hydrogen peroxide sterilizer. Point-to-point registration was applied, and fiducial and target registration errors were computed. Surfaces were extracted from CT scans and Hausdorff distances were derived. Effectiveness of sterilization was determined using Geobacillus stearothermophilus. Fiducial-based registration of CT scans before and after sterilization resulted in a mean fiducial registration error of 0.74 mm; the target registration error in the mouthpiece was 0.15 mm. The Hausdorff distance, describing the maximal deformation of the splint, was 2.51 mm. Ninety percent of point-surface distances were shorter than 0.61 mm, and 95% were shorter than 0.73 mm. No bacterial growth was found after the sterilization process. Hydrogen peroxide-based low-temperature plasma sterilization does not deform the splint, which is the base for correct computer-navigated surgery. Copyright © 2012 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

The practical use of simplicity in developing ground water models

USGS Publications Warehouse

Hill, M.C.

2006-01-01

The advantages of starting with simple models and building complexity slowly can be significant in the development of ground water models. In many circumstances, simpler models are characterized by fewer defined parameters and shorter execution times. In this work, the number of parameters is used as the primary measure of simplicity and complexity; the advantages of shorter execution times also are considered. The ideas are presented in the context of constructing ground water models but are applicable to many fields. Simplicity first is put in perspective as part of the entire modeling process using 14 guidelines for effective model calibration. It is noted that neither very simple nor very complex models generally produce the most accurate predictions and that determining the appropriate level of complexity is an ill-defined process. It is suggested that a thorough evaluation of observation errors is essential to model development. Finally, specific ways are discussed to design useful ground water models that have fewer parameters and shorter execution times.

Neural network fusion: a novel CT-MR aortic aneurysm image segmentation method

NASA Astrophysics Data System (ADS)

Wang, Duo; Zhang, Rui; Zhu, Jin; Teng, Zhongzhao; Huang, Yuan; Spiga, Filippo; Du, Michael Hong-Fei; Gillard, Jonathan H.; Lu, Qingsheng; Liò, Pietro

2018-03-01

Medical imaging examination on patients usually involves more than one imaging modalities, such as Computed Tomography (CT), Magnetic Resonance (MR) and Positron Emission Tomography(PET) imaging. Multimodal imaging allows examiners to benefit from the advantage of each modalities. For example, for Abdominal Aortic Aneurysm, CT imaging shows calcium deposits in the aorta clearly while MR imaging distinguishes thrombus and soft tissues better.1 Analysing and segmenting both CT and MR images to combine the results will greatly help radiologists and doctors to treat the disease. In this work, we present methods on using deep neural network models to perform such multi-modal medical image segmentation. As CT image and MR image of the abdominal area cannot be well registered due to non-affine deformations, a naive approach is to train CT and MR segmentation network separately. However, such approach is time-consuming and resource-inefficient. We propose a new approach to fuse the high-level part of the CT and MR network together, hypothesizing that neurons recognizing the high level concepts of Aortic Aneurysm can be shared across multiple modalities. Such network is able to be trained end-to-end with non-registered CT and MR image using shorter training time. Moreover network fusion allows a shared representation of Aorta in both CT and MR images to be learnt. Through experiments we discovered that for parts of Aorta showing similar aneurysm conditions, their neural presentations in neural network has shorter distances. Such distances on the feature level is helpful for registering CT and MR image.

The effects of in-vehicle tasks and time-gap selection while reclaiming control from adaptive cruise control (ACC) with bus simulator.

PubMed

Lin, Tsang-Wei; Hwang, Sheue-Ling; Su, Jau-Ming; Chen, Wan-Hui

2008-05-01

This research aimed to find out the effects of in-vehicle distractions and time-gap settings with a fix-based bus driving simulator in a following scenario. Professional bus drivers were recruited to perform in-vehicle tasks while driving with adaptive cruise control (ACC) of changeable time-gap settings in freeway traffic. Thirty subjects were divided equally into three groups for different in-vehicle task modes (between subjects), including no task distraction, hands-free, and manual modes. Further, time-gap settings for the experimental ACC were: shorter than 1.0 s, 1.0-1.5 s, 1.5-2.0 s, and longer than 2.0 s (within subjects). Longitudinal (mean headway, forward collision rate, and response time) and lateral control (mean lateral lane position and its standard deviation) performance was assessed. In the results, longitudinal control performance was worsened by both shorter time-gaps and heavier in-vehicle tasks. But the interaction indicated that the harm by heavier in-vehicle distraction could be improved by longer time-gaps. As for the lateral control, it would only be negatively affected by shorter time-gap settings. This research indicates the effects of time-gaps and in-vehicle distraction, as well as the interaction. Proper time-gap selection under different in-vehicle distractions can help avoid accidents and keep safe.

Effect of axial length on laser spot size during photodynamic therapy: an experimental study in monkeys.

PubMed

Kondo, Mineo; Ito, Yasuki; Miyata, Kentaro; Kondo, Nagako; Ishikawa, Kohei; Terasaki, Hiroko

2006-01-01

To investigate the effect of shorter axial length on the laser spot size and laser energy during photodynamic therapy (PDT) in monkeys. Experimental study with four rhesus monkeys. PDT was performed on the normal retina of monkeys whose ocular axial lengths are shorter (19.55 to 20.25 mm) than that of humans. After the PDT, the eyes were enucleated, and the diameter of the irradiated laser spot was measured with a microcaliper. The area of actual laser spot was only 0.56 to 0.61 times of the planned area, which indicated that the laser energy/area was 1.64 to 1.78 times more intense than planned initially. These results are the in vivo demonstration that the diameter of PDT laser spot is smaller for eyes with shorter axial lengths.

Personality Disorder Symptom Severity Predicts Onset of Mood Episodes and Conversion to Bipolar I Disorder in Individuals with Bipolar Spectrum Disorder

PubMed Central

Ng, Tommy H.; Burke, Taylor A.; Stange, Jonathan P.; Walshaw, Patricia D.; Weiss, Rachel B.; Urosevic, Snezana; Abramson, Lyn Y.; Alloy, Lauren B.

2017-01-01

Although personality disorders (PDs) are highly comorbid with bipolar spectrum disorders (BSDs), little longitudinal research has been conducted to examine the prospective impact of PD symptoms on the course of BSDs. The aim of this study is to examine whether PD symptom severity predicts shorter time to onset of bipolar mood episodes and conversion to bipolar I disorder over time among individuals with less severe BSDs. Participants (n = 166) with bipolar II disorder, cyclothymia, or bipolar disorder not otherwise specified completed diagnostic interview assessments of PD symptoms and self-report measures of mood symptoms at baseline. They were followed prospectively with diagnostic interviews every four months for an average of 3.02 years. Cox proportional hazard regression analyses indicated that overall PD symptom severity significantly predicted shorter time to onset of hypomanic (hazard ratio [HR]= 1.42; p < .001) and major depressive episodes (HR = 1.51; p < .001) and conversion to bipolar I disorder (HR = 2.51; p < .001), after controlling for mood symptoms. Results also suggested that cluster B severity predicted shorter time to onset of hypomanic episodes (HR = 1.38; p = .002) and major depressive episodes (HR = 1.35; p = .01) and conversion to bipolar I disorder (HR = 2.77; p < .001), whereas cluster C severity (HR= 1.56; p < .001) predicted shorter time to onset of major depressive episodes. These results support predisposition models in suggesting that PD symptoms may act as a risk factor for a more severe course of BSDs. PMID:28368159

Personality disorder symptom severity predicts onset of mood episodes and conversion to bipolar I disorder in individuals with bipolar spectrum disorder.

PubMed

Ng, Tommy H; Burke, Taylor A; Stange, Jonathan P; Walshaw, Patricia D; Weiss, Rachel B; Urosevic, Snezana; Abramson, Lyn Y; Alloy, Lauren B

2017-04-01

Although personality disorders (PDs) are highly comorbid with bipolar spectrum disorders (BSDs), little longitudinal research has been conducted to examine the prospective impact of PD symptoms on the course of BSDs. The aim of this study is to examine whether PD symptom severity predicts shorter time to onset of bipolar mood episodes and conversion to bipolar I disorder over time among individuals with less severe BSDs. Participants (n = 166) with bipolar II disorder, cyclothymia, or bipolar disorder not otherwise specified completed diagnostic interview assessments of PD symptoms and self-report measures of mood symptoms at baseline. They were followed prospectively with diagnostic interviews every 4 months for an average of 3.02 years. Cox proportional hazard regression analyses indicated that overall PD symptom severity significantly predicted shorter time to onset of hypomanic (hazard ratio [HR] = 1.42; p < .001) and major depressive episodes (HR = 1.51; p < .001) and conversion to bipolar I disorder (HR = 2.51; p < .001), after controlling for mood symptoms. Results also suggested that cluster B severity predicted shorter time to onset of hypomanic episodes (HR = 1.38; p = .002) and major depressive episodes (HR = 1.35; p = .01) and conversion to bipolar I disorder (HR = 2.77; p < .001), whereas cluster C severity (HR = 1.56; p < .001) predicted shorter time to onset of major depressive episodes. These results support predisposition models in suggesting that PD symptoms may act as a risk factor for a more severe course of BSDs. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Pessimistic orientation in relation to telomere length in older men: the VA Normative Aging Study

PubMed Central

Ikeda, Ai; Schwartz, Joel; Peters, Junenette L.; Baccarelli, Andrea A.; Hoxha, Mirjam; Dioni, Laura; Spiro, Avron; Sparrow, David; Vokonas, Pantel; Kubzansky, Laura D.

2014-01-01

Background Recent research suggests pessimistic orientation is associated with shorter leukocyte telomere length (LTL). However, this is the first study to look not only at effects of pessimistic orientation on average LTL at multiple time points, but also at effects on the rate of change in LTL over time. Methods Participants were older men from the VA Normative Aging Study (n=490). The Life Orientation Test (LOT) was used to measure optimistic and pessimistic orientations at study baseline, and relative LTL by telomere to single copy gene ratio (T:S ratio) was obtained repeatedly over the course of the study (1999-2008). A total of 1,010 observations were included in the analysis. Linear mixed effect models with a random subject intercept were used to estimate associations. Results Higher pessimistic orientation scores were associated with shorter average LTL (percent difference by 1-SD increase in pessimistic orientation (95% CI): -3.08 (-5.62, -0.46)), and the finding was maintained after adjusting for the higher likelihood that healthier individuals return for follow-up visits (-3.44 (-5.95,-0.86)). However, pessimistic orientation scores were not associated with rate of change in LTL over time. No associations were found between overall optimism and optimistic orientation subscale scores and LTL. Conclusion Higher pessimistic orientation scores were associated with shorter LTL in older men. While there was no evidence that pessimistic orientation was associated with rate of change in LTL over time, higher levels of pessimistic orientation were associated with shorter LTL at baseline and this association persisted over time. PMID:24636503

Accurate Classification of Diminutive Colorectal Polyps Using Computer-Aided Analysis.

PubMed

Chen, Peng-Jen; Lin, Meng-Chiung; Lai, Mei-Ju; Lin, Jung-Chun; Lu, Henry Horng-Shing; Tseng, Vincent S

2018-02-01

Narrow-band imaging is an image-enhanced form of endoscopy used to observed microstructures and capillaries of the mucosal epithelium which allows for real-time prediction of histologic features of colorectal polyps. However, narrow-band imaging expertise is required to differentiate hyperplastic from neoplastic polyps with high levels of accuracy. We developed and tested a system of computer-aided diagnosis with a deep neural network (DNN-CAD) to analyze narrow-band images of diminutive colorectal polyps. We collected 1476 images of neoplastic polyps and 681 images of hyperplastic polyps, obtained from the picture archiving and communications system database in a tertiary hospital in Taiwan. Histologic findings from the polyps were also collected and used as the reference standard. The images and data were used to train the DNN. A test set of images (96 hyperplastic and 188 neoplastic polyps, smaller than 5 mm), obtained from patients who underwent colonoscopies from March 2017 through August 2017, was then used to test the diagnostic ability of the DNN-CAD vs endoscopists (2 expert and 4 novice), who were asked to classify the images of the test set as neoplastic or hyperplastic. Their classifications were compared with findings from histologic analysis. The primary outcome measures were diagnostic accuracy, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and diagnostic time. The accuracy, sensitivity, specificity, PPV, NPV, and diagnostic time were compared among DNN-CAD, the novice endoscopists, and the expert endoscopists. The study was designed to detect a difference of 10% in accuracy by a 2-sided McNemar test. In the test set, the DNN-CAD identified neoplastic or hyperplastic polyps with 96.3% sensitivity, 78.1% specificity, a PPV of 89.6%, and a NPV of 91.5%. Fewer than half of the novice endoscopists classified polyps with a NPV of 90% (their NPVs ranged from 73.9% to 84.0%). DNN-CAD classified polyps as neoplastic or hyperplastic in 0.45 ± 0.07 seconds-shorter than the time required by experts (1.54 ± 1.30 seconds) and nonexperts (1.77 ± 1.37 seconds) (both P < .001). DNN-CAD classified polyps with perfect intra-observer agreement (kappa score of 1). There was a low level of intra-observer and inter-observer agreement in classification among endoscopists. We developed a system called DNN-CAD to identify neoplastic or hyperplastic colorectal polyps less than 5 mm. The system classified polyps with a PPV of 89.6%, and a NPV of 91.5%, and in a shorter time than endoscopists. This deep-learning model has potential for not only endoscopic image recognition but for other forms of medical image analysis, including sonography, computed tomography, and magnetic resonance images. Copyright © 2018 AGA Institute. Published by Elsevier Inc. All rights reserved.

Efficient Computing Budget Allocation for Finding Simplest Good Designs

PubMed Central

Jia, Qing-Shan; Zhou, Enlu; Chen, Chun-Hung

2012-01-01

In many applications some designs are easier to implement, require less training data and shorter training time, and consume less storage than the others. Such designs are called simple designs, and are usually preferred over complex ones when they all have good performance. Despite the abundant existing studies on how to find good designs in simulation-based optimization (SBO), there exist few studies on finding simplest good designs. We consider this important problem in this paper, and make the following contributions. First, we provide lower bounds for the probabilities of correctly selecting the m simplest designs with top performance, and selecting the best m such simplest good designs, respectively. Second, we develop two efficient computing budget allocation methods to find m simplest good designs and to find the best m such designs, respectively; and show their asymptotic optimalities. Third, we compare the performance of the two methods with equal allocations over 6 academic examples and a smoke detection problem in wireless sensor networks. We hope that this work brings insight to finding the simplest good designs in general. PMID:23687404

An investigation of bread-baking process in a pilot-scale electrical heating oven using computational fluid dynamics.

PubMed

Anishaparvin, A; Chhanwal, N; Indrani, D; Raghavarao, K S M S; Anandharamakrishnan, C

2010-01-01

A computational fluid dynamics (CFD) model was developed for bread-baking process in a pilot-scale baking oven to find out the effect of hot air distribution and placement of bread on temperature and starch gelatinization index of bread. In this study, product (bread) simulation was carried out with different placements of bread. Simulation results were validated with experimental measurements of bread temperature. This study showed that nonuniform air flow pattern inside the oven cavity leads to uneven temperature distribution. The study with respect to placement of bread showed that baking of bread in upper trays required shorter baking time and gelatinization index compared to those in the bottom tray. The upper tray bread center reached 100 °C at 1200 s, whereas starch gelatinization completed within 900 s, which was the minimum baking index. Moreover, the heat penetration and starch gelatinization were higher along the sides of the bread as compared to the top and bottom portions of the bread. © 2010 Institute of Food Technologists®

Estimating Temperature Rise Due to Flashlamp Heating Using Irreversible Temperature Indicators

NASA Technical Reports Server (NTRS)

Koshti, Ajay M.

1999-01-01

One of the nondestructive thermography inspection techniques uses photographic flashlamps. The flashlamps provide a short duration (about 0.005 sec) heat pulse. The short burst of energy results in a momentary rise in the surface temperature of the part. The temperature rise may be detrimental to the top layer of the part being exposed. Therefore, it is necessary to ensure the nondestructive nature of the technique. Amount of the temperature rise determines whether the flashlamp heating would be detrimental to the part. A direct method for the temperature measurement is to use of an infrared pyrometer that has much shorter response time than the flash duration. In this paper, an alternative technique is given using the irreversible temperature 'indicators. This is an indirect technique and it measures the temperature rise on the irreversible temperature indicators and computes the incident heat flux. Once the heat flux is known, the temperature rise on the part can be computed. A wedge shaped irreversible temperature indicator for measuring the heat flux is proposed. A procedure is given to use the wedge indicator.

Decisions in Motion: Decision Dynamics during Intertemporal Choice reflect Subjective Evaluation of Delayed Rewards

PubMed Central

O’Hora, Denis; Carey, Rachel; Kervick, Aoife; Crowley, David; Dabrowski, Maciej

2016-01-01

People tend to discount rewards or losses that occur in the future. Such delay discounting has been linked to many behavioral and health problems, since people choose smaller short-term gains over greater long-term gains. We investigated whether the effect of delays on the subjective value of rewards is expressed in how people move when they make choices. Over 600 patrons of the RISK LAB exhibition hosted by the Science Gallery DublinTM played a short computer game in which they used a computer mouse to choose between amounts of money at various delays. Typical discounting effects were observed and decision dynamics indicated that choosing smaller short-term rewards became easier (i.e., shorter response times, tighter trajectories, less vacillation) as the delays until later rewards increased. Based on a sequence of choices, subjective values of delayed outcomes were estimated and decision dynamics during initial choices predicted these values. Decision dynamics are affected by subjective values of available options and thus provide a means to estimate such values. PMID:26867497

Multi-class ERP-based BCI data analysis using a discriminant space self-organizing map.

PubMed

Onishi, Akinari; Natsume, Kiyohisa

2014-01-01

Emotional or non-emotional image stimulus is recently applied to event-related potential (ERP) based brain computer interfaces (BCI). Though the classification performance is over 80% in a single trial, a discrimination between those ERPs has not been considered. In this research we tried to clarify the discriminability of four-class ERP-based BCI target data elicited by desk, seal, spider images and letter intensifications. A conventional self organizing map (SOM) and newly proposed discriminant space SOM (ds-SOM) were applied, then the discriminabilites were visualized. We also classify all pairs of those ERPs by stepwise linear discriminant analysis (SWLDA) and verify the visualization of discriminabilities. As a result, the ds-SOM showed understandable visualization of the data with a shorter computational time than the traditional SOM. We also confirmed the clear boundary between the letter cluster and the other clusters. The result was coherent with the classification performances by SWLDA. The method might be helpful not only for developing a new BCI paradigm, but also for the big data analysis.

Dynamics of retinal photocoagulation and rupture

NASA Astrophysics Data System (ADS)

Sramek, Christopher; Paulus, Yannis; Nomoto, Hiroyuki; Huie, Phil; Brown, Jefferson; Palanker, Daniel

2009-05-01

In laser retinal photocoagulation, short (<20 ms) pulses have been found to reduce thermal damage to the inner retina, decrease treatment time, and minimize pain. However, the safe therapeutic window (defined as the ratio of power for producing a rupture to that of mild coagulation) decreases with shorter exposures. To quantify the extent of retinal heating and maximize the therapeutic window, a computational model of millisecond retinal photocoagulation and rupture was developed. Optical attenuation of 532-nm laser light in ocular tissues was measured, including retinal pigment epithelial (RPE) pigmentation and cell-size variability. Threshold powers for vaporization and RPE damage were measured with pulse durations ranging from 1 to 200 ms. A finite element model of retinal heating inferred that vaporization (rupture) takes place at 180-190°C. RPE damage was accurately described by the Arrhenius model with activation energy of 340 kJ/mol. Computed photocoagulation lesion width increased logarithmically with pulse duration, in agreement with histological findings. The model will allow for the optimization of beam parameters to increase the width of the therapeutic window for short exposures.

FIT: statistical modeling tool for transcriptome dynamics under fluctuating field conditions

PubMed Central

Iwayama, Koji; Aisaka, Yuri; Kutsuna, Natsumaro

2017-01-01

Abstract Motivation: Considerable attention has been given to the quantification of environmental effects on organisms. In natural conditions, environmental factors are continuously changing in a complex manner. To reveal the effects of such environmental variations on organisms, transcriptome data in field environments have been collected and analyzed. Nagano et al. proposed a model that describes the relationship between transcriptomic variation and environmental conditions and demonstrated the capability to predict transcriptome variation in rice plants. However, the computational cost of parameter optimization has prevented its wide application. Results: We propose a new statistical model and efficient parameter optimization based on the previous study. We developed and released FIT, an R package that offers functions for parameter optimization and transcriptome prediction. The proposed method achieves comparable or better prediction performance within a shorter computational time than the previous method. The package will facilitate the study of the environmental effects on transcriptomic variation in field conditions. Availability and Implementation: Freely available from CRAN (https://cran.r-project.org/web/packages/FIT/). Contact: anagano@agr.ryukoku.ac.jp Supplementary information: Supplementary data are available at Bioinformatics online PMID:28158396

Employment and work schedule are related to telomere length in women

PubMed Central

Parks, C G; DeRoo, L A; Miller, D B; McCanlies, E C; Cawthon, R M; Sandler, D P

2011-01-01

Objectives To examine the association of employment and work schedule with shorter DNA telomeres, a marker of cellular ageing and disease risk factor, and consider whether differences were related to health, behaviours and sociodemographic factors, or varied by stress levels or menopausal status. Methods This cross-sectional analysis of 608 women aged 35–74 in the Sister Study examined determinants of relative telomere length (rTL) measured by quantitative PCR in leucocyte DNA. Age-adjusted regression models estimated base pair (bp) rTL differences for current and lifetime schedule characteristics (ie, part-time, full-time or overtime hours; multiple jobs; irregular hours; shiftwork; work at night). Covariates included race, smoking, perceived stress, sleep, physical activity, health and menopausal status, education, marital status, live births, children under 18, measured body mass index and urinary stress hormones. Results Compared with non-employed women with moderate or substantial past work histories (n=190), those currently working full-time (n=247; median 40 h/week) had a shorter rTL, an age-adjusted difference of −329 bp (95% CI −110 to −548). Longer-duration full-time work was also associated with shorter rTL (age-adjusted difference of −472 bp, 95% CI −786 to −158 for 20+ vs 1–5 years). Findings were not explained by health and demographic covariates. However, rTL differences for working at least full-time were greater in women with higher stress and epinephrine levels. Conclusions Current and long-term full-time work were associated with shorter rTL, with differences of similar magnitude to smoking and history of heart disease or diabetes. Longitudinal data with specific stress measures are needed to further evaluate the impact of work schedule on rTL. PMID:21540175

Employment and work schedule are related to telomere length in women.

PubMed

Parks, C G; DeRoo, L A; Miller, D B; McCanlies, E C; Cawthon, R M; Sandler, D P

2011-08-01

To examine the association of employment and work schedule with shorter DNA telomeres, a marker of cellular ageing and disease risk factor, and consider whether differences were related to health, behaviours and sociodemographic factors, or varied by stress levels or menopausal status. This cross-sectional analysis of 608 women aged 35-74 in the Sister Study examined determinants of relative telomere length (rTL) measured by quantitative PCR in leucocyte DNA. Age-adjusted regression models estimated base pair (bp) rTL differences for current and lifetime schedule characteristics (ie, part-time, full-time or overtime hours; multiple jobs; irregular hours; shiftwork; work at night). Covariates included race, smoking, perceived stress, sleep, physical activity, health and menopausal status, education, marital status, live births, children under 18, measured body mass index and urinary stress hormones. Compared with non-employed women with moderate or substantial past work histories (n=190), those currently working full-time (n=247; median 40 h/week) had a shorter rTL, an age-adjusted difference of -329 bp (95% CI -110 to -548). Longer-duration full-time work was also associated with shorter rTL (age-adjusted difference of -472 bp, 95% CI -786 to -158 for 20+ vs 1-5 years). Findings were not explained by health and demographic covariates. However, rTL differences for working at least full-time were greater in women with higher stress and epinephrine levels. Current and long-term full-time work were associated with shorter rTL, with differences of similar magnitude to smoking and history of heart disease or diabetes. Longitudinal data with specific stress measures are needed to further evaluate the impact of work schedule on rTL.

Icon flickering, flicker rate, and color combinations of an icon's symbol/background in visual search performance.

PubMed

Huang, Kuo-Chen; Chiang, Shu-Ying; Chen, Chen-Fu

2008-02-01

The effects of color combinations of an icon's symbol/background and components of flicker and flicker rate on visual search performance on a liquid crystal display screen were investigated with 39 subjects who searched for a target icon in a circular stimulus array (diameter = 20 cm) including one target and 19 distractors. Analysis showed that the icon's symbol/background color significantly affected search time. The search times for icons with black/red and white/blue were significantly shorter than for white/yellow, black/yellow, and black/blue. Flickering of different components of the icon significantly affected the search time. Search time for an icon's border flickering was shorter than for an icon symbol flickering; search for flicker rates of 3 and 5 Hz was shorter than that for 1 Hz. For icon's symbol/background color combinations, search error rate for black/blue was greater than for black/red and white/blue combinations, and the error rate for an icon's border flickering was lower than for an icon's symbol flickering. Interactions affected search time and error rate. Results are applicable to design of graphic user interfaces.

78 FR 59641 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Revisions to Headboat Reporting...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-09-27

... revisions would require fishing records to be submitted electronically (via computer or Internet) on a weekly basis or at intervals shorter than a week if notified by the NMFS' Southeast Fisheries Science Center (SEFSC) Science and Research Director (SRD), and would prohibit headboats from continuing to fish...

A Novel Method for Prediction of Nonlinear Aeroelastic Responses

DTIC Science & Technology

2010-01-01

where a and b are respectively the lengths of the longer and shorter sides ( Ugural and Fenster, 1981). Y Z X Figure 3.5: Twisted beam with 100×5×10...improved trans- verse shear. Computer Methods in Applied Mechanics and Engineering 50 (1), 7–91. cauta. Ugural , A. C. and S. K. Fenster (1981

Computed Tomographic Angiography of the Pancreas in Cats with Chronic Diabetes Mellitus Compared to Normal Cats.

PubMed

Secrest, S; Sharma, A; Bugbee, A

2018-03-02

Diabetes mellitus (DM) is a common endocrinopathy in cats. No known diagnostic test or patient characteristic at the time of diagnosis can predict likely disease course, unlike in people in whom computed tomographic angiography (CTA) is used. No published data exist regarding the CTA appearance of the pancreas in cats with DM, and thus, it is unknown what if any CTA variables should be further assessed for associations with pancreatic endocrine function. A significant difference in pancreatic attenuation, volume, and size will be identified between normal cats and those with chronic DM on CTA. Ten healthy control cats and 15 cats with naturally occurring DM present for >12 months. Prospective cross-sectional study comparing pancreatic attenuation, enhancement pattern, size, volume, pancreatic volume-to-body weight ratio (V:BW), pancreatic arterial: portal phase ratio (A:P), time-to-arterial enhancement, and time-to-peak portal enhancement on CTA between sedated healthy control cats and those with chronic DM. The pancreas in cats with chronic DM was significantly larger, had higher volume, higher V:BW, and shorter time-to-peak portal enhancement on CTA when compared to normal cats. Peak portal enhancement time, pancreatic size, pancreatic volume, and V:BW can be used to differentiate normal sedated cats from those with chronic DM by CTA. These variables warrant further investigation to identify possible associations with endocrine function. Copyright © 2017 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.

The effects of publishing emergency department wait time on patient utilization patterns in a community with two emergency department sites: a retrospective, quasi-experiment design.

PubMed

Xie, Bin; Youash, Sabrina

2011-06-14

Providing emergency department (ED) wait time information to the public has been suggested as a mechanism to reduce lengthy ED wait times (by enabling patients to select the ED site with shorter wait time), but the effects of such a program have not been evaluated. We evaluated the effects of such a program in a community with two ED sites. Descriptive statistics for wait times of the two sites before and after the publication of wait time information were used to evaluate the effects of the publication of wait time information on wait times. Multivariate logistical regression was used to test whether or not individual patients used published wait time to decide which site to visit. We found that the rates of wait times exceeding 4 h, and the 95th percentile of wait times in the two sites decreased after the publication of wait time information, even though the average wait times experienced a slight increase. We also found that after controlling for other factors, the site with shorter wait time had a higher likelihood of being selected after the publication of wait time information, but there was no such relationship before the publication. These findings were consistent with the hypothesis that the publication of wait time information leads to patients selecting the site with shorter wait time. While publishing ED wait time information did not improve average wait time, it reduced the rates of lengthy wait times.

Impact of IT on health care professionals: changes in work and the productivity paradox.

PubMed

Hebert, M A

1998-05-01

Health care organizations are under increasing pressure to become more efficient while at the same time maintaining or improving the quality of care. Information technology (IT), with its potential to increase efficiency, accuracy and accessibility of information, has been expected to play an important role in supporting these changes. We report the impact of patient care information systems on health care professionals in five community hospitals. The study framework incorporated both quality of care in Donabedian's elements of structure-process-outcome and Grusec's three levels of IT impact: direct substitution, proceduralization and new capabilities. The study results suggest that, for specific tasks, IT increased efficiency and productivity--a single employee was able to complete more tasks. However, this produced other consequences not predicted. Participants noted this change did not 'free up time' to spend with patients, but meant there were potentially more opportunities to provide services and more tasks to complete. Other effects included: reduced job satisfaction as more time was spent on the computer; less frequent interactions with patients and for shorter duration; and an increasingly 'visible' accountability as performance was easily monitored. There were also changes in roles and responsibilities as the computer enabled tasks to be carried out from a number of locations and by a variety of personnel. When innovations are introduced into organizations there are both expected and unexpected consequences. Increased awareness of the interactive relationship between computer users and the technology helps organizations better understand why results do, or do not, occur. One must look beyond just simply increasing productivity by replacing manual tasks with automated ones, to examining how the changes influence the nature of work and relationships within the organization.

Subglacial drainage effects on surface motion on a small surge type alpine glacier on the St. Elias range, Yukon Territory, Canada.

NASA Astrophysics Data System (ADS)

Rada, C.; Schoof, C.; King, M. A.; Flowers, G. E.; Haber, E.

2017-12-01

Subglacial drainage is known to play an important role in glacier dynamics trough its influence on basal sliding. However, drainage is also one of the most poorly understood process in glacier flow due to the difficulties of observing, identifying and modeling the physics involved. In an effort to improve understanding of subglacial processes, we have monitored a small, approximately 100 m thick surge-type alpine glacier for nine years. Over 300 boreholes were instrumented with pressure transducers over a 0.5 km² in its upper ablation area, in addition to a weather station and a permanent GPS array consisting on 16 dual-frequency receivers within the study area. We study the influence of the subglacial drainage system on the glacier surface velocity. However, pressure variations in the drainage system during the melt season are dominated by diurnal oscillations.Therefore, GPS solutions have to be computed at sub-diurnal time intervals in order to explore the effects of transient diurnal pressure variations. Due to the small displacements of the surface of the glacier over those periods (4-10 cm/day), sub-diurnal solutions are dominated by errors, making it impossible to observe the diurnal variations in glacier motion. We have found that the main source of error is GPS multipath. This error source does largely cancel out when solutions are computed over 24 hour periods (or more precisely, over a sidereal day), but solution precisions decrease quickly when computed over shorter periods of time. Here we present an inverse problem approach to remove GPS multipath errors on glaciers, and use the reconstructed glacier motion to explore how the subglacial drainage morphology and effective pressure influence glacier dynamics at multiple time scales.

Development of a QFD-based expert system for CNC turning centre selection

NASA Astrophysics Data System (ADS)

Prasad, Kanika; Chakraborty, Shankar

2015-12-01

Computer numerical control (CNC) machine tools are automated devices capable of generating complicated and intricate product shapes in shorter time. Selection of the best CNC machine tool is a critical, complex and time-consuming task due to availability of a wide range of alternatives and conflicting nature of several evaluation criteria. Although, the past researchers had attempted to select the appropriate machining centres using different knowledge-based systems, mathematical models and multi-criteria decision-making methods, none of those approaches has given due importance to the voice of customers. The aforesaid limitation can be overcome using quality function deployment (QFD) technique, which is a systematic approach for integrating customers' needs and designing the product to meet those needs first time and every time. In this paper, the adopted QFD-based methodology helps in selecting CNC turning centres for a manufacturing organization, providing due importance to the voice of customers to meet their requirements. An expert system based on QFD technique is developed in Visual BASIC 6.0 to automate the CNC turning centre selection procedure for different production plans. Three illustrative examples are demonstrated to explain the real-time applicability of the developed expert system.

Vocal release time: a quantification of vocal offset.

PubMed

Watson, Ben C; Roark, Rick M; Baken, R J

2012-11-01

To determine the vocal release time (VRT) for linguistically unconstrained voice offsets in a healthy young adult population. Sound pressure (SP) and electroglottographic (EGG) recordings were obtained for 57 female and 55 male subjects while producing multiple tokens of three tasks (sustained /ɑ:/, "always," and "hallways") at comfortable pitch and loudness. SP and EGG signals were digitally time reversed and generalized sinusoidal models of the SP and EGG signals were obtained to compare rates of amplitude change. VRT was computed from the time lag of the cross-correlation function. Adjusted mean VRT values were significantly greater for females than for males. There was no systematic effect of age on VRT. However, 25-29-year old and >40 year old females showed shorter VRT values than the youngest female age group. Normative data are presented for a new measure of the duration of vocal offset, VRT. Acquisition of this measure requires little user intervention, thereby minimizing effects of subjective decision making. Comparison with previously reported vocal attack time (VAT) values for the same population suggests phenomenological differences between linguistically and physiologically constrained voice onsets and unconstrained voice offsets. Copyright © 2012 The Voice Foundation. Published by Mosby, Inc. All rights reserved.

Photonic Design: From Fundamental Solar Cell Physics to Computational Inverse Design

NASA Astrophysics Data System (ADS)

Miller, Owen Dennis

Photonic innovation is becoming ever more important in the modern world. Optical systems are dominating shorter and shorter communications distances, LED's are rapidly emerging for a variety of applications, and solar cells show potential to be a mainstream technology in the energy space. The need for novel, energy-efficient photonic and optoelectronic devices will only increase. This work unites fundamental physics and a novel computational inverse design approach towards such innovation. The first half of the dissertation is devoted to the physics of high-efficiency solar cells. As solar cells approach fundamental efficiency limits, their internal physics transforms. Photonic considerations, instead of electronic ones, are the key to reaching the highest voltages and efficiencies. Proper photon management led to Alta Device's recent dramatic increase of the solar cell efficiency record to 28.3%. Moreover, approaching the Shockley-Queisser limit for any solar cell technology will require light extraction to become a part of all future designs. The second half of the dissertation introduces inverse design as a new computational paradigm in photonics. An assortment of techniques (FDTD, FEM, etc.) have enabled quick and accurate simulation of the "forward problem" of finding fields for a given geometry. However, scientists and engineers are typically more interested in the inverse problem: for a desired functionality, what geometry is needed? Answering this question breaks from the emphasis on the forward problem and forges a new path in computational photonics. The framework of shape calculus enables one to quickly find superior, non-intuitive designs. Novel designs for optical cloaking and sub-wavelength solar cell applications are presented.

Shorter Perceived Outpatient MRI Wait Times Associated With Higher Patient Satisfaction.

PubMed

Holbrook, Anna; Glenn, Harold; Mahmood, Rabia; Cai, Qingpo; Kang, Jian; Duszak, Richard

2016-05-01

The aim of this study was to assess differences in perceived versus actual wait times among patients undergoing outpatient MRI examinations and to correlate those times with patient satisfaction. Over 15 weeks, 190 patients presenting for outpatient MR in a radiology department in which "patient experience" is one of the stated strategic priorities were asked to (1) estimate their wait times for various stages in the imaging process and (2) state their satisfaction with their imaging experience. Perceived times were compared with actual electronic time stamps. Perceived and actual times were compared and correlated with standardized satisfaction scores using Kendall τ correlation. The mean actual wait time between patient arrival and examination start was 53.4 ± 33.8 min, whereas patients perceived a mean wait time of 27.8 ± 23.1 min, a statistically significant underestimation of 25.6 min (P < .001). Both shorter actual and perceived wait times at all points during patient encounters were correlated with higher satisfaction scores (P < .001). Patients undergoing outpatient MR examinations in an environment designed to optimize patient experience underestimated wait times at all points during their encounters. Shorter perceived and actual wait times were both correlated with higher satisfaction scores. As satisfaction surveys play a larger role in an environment of metric transparency and value-based payments, better understanding of such factors will be increasingly important. Copyright © 2016 American College of Radiology. Published by Elsevier Inc. All rights reserved.

Pre-hospital electrocardiogram triage with telemedicine near halves time to treatment in STEMI: A meta-analysis and meta-regression analysis of non-randomized studies.

PubMed

Brunetti, Natale Daniele; De Gennaro, Luisa; Correale, Michele; Santoro, Francesco; Caldarola, Pasquale; Gaglione, Antonio; Di Biase, Matteo

2017-04-01

A shorter time to treatment has been shown to be associated with lower mortality rates in acute myocardial infarction (AMI). Several strategies have been adopted with the aim to reduce any delay in diagnosis of AMI: pre-hospital triage with telemedicine is one of such strategies. We therefore aimed to measure the real effect of pre-hospital triage with telemedicine in case of AMI in a meta-analysis study. We performed a meta-analysis of non-randomized studies with the aim to quantify the exact reduction of time to treatment achieved by pre-hospital triage with telemedicine. Data were pooled and compared by relative time reduction and 95% C.I.s. A meta-regression analysis was performed in order to find possible predictors of shorter time to treatment. Eleven studies were selected and finally evaluated in the study. The overall relative reduction of time to treatment with pre-hospital triage and telemedicine was -38/-40% (p<0.001). Absolute time reduction was significantly correlated to time to treatment in the control groups (p<0.001), while relative time reduction was independent. A non-significant trend toward shorter relative time reductions was observed over years. Pre-hospital triage with telemedicine is associated with a near halved time to treatment in AMI. The benefit is larger in terms of absolute time to treatment reduction in populations with larger delays to treatment. Copyright © 2017 Elsevier B.V. All rights reserved.

Drought impacts on vegetation activity in the Mediterranean region: An assessment using remote sensing data and multi-scale drought indicators

NASA Astrophysics Data System (ADS)

Gouveia, C. M.; Trigo, R. M.; Beguería, S.; Vicente-Serrano, S. M.

2017-04-01

The present work analyzes the drought impacts on vegetation over the entire Mediterranean basin, with the purpose of determining the vegetation communities, regions and seasons at which vegetation is driven by drought. Our approach is based on the use of remote sensing data and a multi-scalar drought index. Correlation maps between fields of monthly Normalized Difference Vegetation Index (NDVI) and the Standardized Precipitation-Evapotranspiration Index (SPEI) at different time scales (1-24 months) were computed for representative months of winter (Feb), spring (May), summer (Aug) and fall (Nov). Results for the period from 1982 to 2006 show large areas highly controlled by drought, although presenting high spatial and seasonal differences, with a maximum influence in August and a minimum in February. The highest correlation values are observed in February for 3 months' time scale and in May for 6 and 12 months. The higher control of drought on vegetation in February and May is obtained mainly over the drier vegetation communities (Mediterranean Dry and Desertic) at shorter time scales (3 to 9 months). Additionally, in February the impact of drought on vegetation is lower for Temperate Oceanic and Continental vegetation types and takes place at longer time scales (18-24). The dependence of drought time-scale response with water balance, as obtained through a simple difference between precipitation and reference evapotranspiration, varies with vegetation communities. During February and November low water balance values correspond to shorter time scales over dry vegetation communities, whereas high water balance values implies longer time scales over Temperate Oceanic and Continental areas. The strong control of drought on vegetation observed for Mediterranean Dry and Desertic vegetation types located over areas with high negative values of water balance emphasizes the need for an early warning drought system covering the entire Mediterranean basin. We are confident that these results will provide a useful tool for drought management plans and play a relevant role in mitigating the impact of drought episodes.

Maternal and Fetal Effect of Misgav Ladach Cesarean Section in Nigerian Women: A Randomized Control Study

PubMed Central

Ezechi, OC; Ezeobi, PM; Gab-Okafor, CV; Edet, A; Nwokoro, CA; Akinlade, A

2013-01-01

Background: The poor utilisation of the Misgav-Ladach (ML) caesarean section method in our environment despite its proven advantage has been attributed to several factors including its non-evaluation. A well designed and conducted trial is needed to provide evidence to convince clinician of its advantage over Pfannenstiel based methods. Aim: To evaluate the outcome of ML based caesarean section among Nigerian women. Subjects and Methods: Randomised controlled open label study of 323 women undergoing primary caesarean section in Lagos Nigeria. The women were randomised to either ML method or Pfannenstiel based (PB) caesarean section technique using computer generated random numbers. Results: The mean duration of surgery (P < 0.001), time to first bowel motion (P = 0.01) and ambulation (P < 0.001) were significantly shorter in the ML group compared to PB group. Postoperative anaemia (P < 0.01), analgesic needs (P = 0.02), extra suture use, estimated blood loss (P < 0.01) and post-operative complications (P = 0.001) were significantly lower in the ML group compared to PB group. Though the mean hospital stay was shorter (5.8 days) in the ML group as against 6.0 days, the difference was not significant statistically (P = 0.17). Of the fetal outcome measures compared, it was only in the fetal extraction time that there was significant difference between the two groups (P = 0.001). The mean fetal extraction time was 162 sec in ML group compared to 273 sec in the PB group. Conclusions: This study confirmed the already established benefit of ML techniques in Nigerian women, as it relates to the postoperative outcomes, duration of surgery, and fetal extraction time. The technique is recommended to clinicians as its superior maternal and fetal outcome and cost saving advantage makes it appropriate for use in poor resource setting. PMID:24380012

Intrafraction Motion in Stereotactic Body Radiation Therapy for Non-Small Cell Lung Cancer: Intensity Modulated Radiation Therapy Versus Volumetric Modulated Arc Therapy

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

Rossi, Maddalena M.G.; Peulen, Heike M.U.; Belderbos, Josè S.A.

Purpose: Stereotactic body radiation therapy (SBRT) for early-stage inoperable non-small cell lung cancer (NSCLC) patients delivers high doses that require high-precision treatment. Typically, image guidance is used to minimize day-to-day target displacement, but intrafraction position variability is often not corrected. Currently, volumetric modulated arc therapy (VMAT) is replacing intensity modulated radiation therapy (IMRT) in many departments because of its shorter delivery time. This study aimed to evaluate whether intrafraction variation in VMAT patients is reduced in comparison with patients treated with IMRT. Methods and Materials: NSCLC patients (197 IMRT and 112 VMAT) treated with a frameless SBRT technique to amore » prescribed dose of 3 × 18 Gy were evaluated. Image guidance for both techniques was identical: pretreatment cone beam computed tomography (CBCT) (CBCT{sub precorr}) for setup correction followed immediately before treatment by postcorrection CBCT (CBCT{sub postcorr}) for verification. Then, after either a noncoplanar IMRT technique or a VMAT technique, a posttreatment (CBCT{sub postRT}) scan was acquired. The CBCT{sub postRT} and CBCT{sub postcorr} scans were then used to evaluate intrafraction motion. Treatment delivery times, systematic (Σ) and random (σ) intrafraction variations, and associated planning target volume (PTV) margins were calculated. Results: The median treatment delivery time was significantly reduced by 20 minutes (range, 32-12 minutes) using VMAT compared with noncoplanar IMRT. Intrafraction tumor motion was significantly larger for IMRT in all directions up to 0.5 mm systematic (Σ) and 0.7 mm random (σ). The required PTV margins for IMRT and VMAT differed by less than 0.3 mm. Conclusion: VMAT-based SBRT for NSCLC was associated with significantly shorter delivery times and correspondingly smaller intrafraction motion compared with noncoplanar IMRT. However, the impact on the required PTV margin was small.« less

[Efficacy of Sacroiliac Joint Anterior Approach with Double Reconstruction Plate and Computer Assisted Navigation Percutaneous Sacroiliac Screw for Treating Tile C1 Pelvic Fractures].

PubMed

Tan, Zhen; Fang, Yue; Zhang, Hui; Liu, Lei; Xiang, Zhou; Zhong, Gang; Huang, Fu-Guo; Wang, Guang-Lin

2017-09-01

To compare the efficacy of sacroiliac joint anterior approach with double reconstruction plate and computer assisted navigation percutaneous sacroiliac screw for treating Tile C1 pelvic fractures. Fifty patients with pelvic Tile C1 fractures were randomly divided into two groups ( n =25 for each) in the orthopedic department of West China Hospital of Sichuan University from December 2012 to November 2014. Patients in group A were treated by sacroiliac joint dislocation with anterior plate fixation. Patients in group B were treated with computerized navigation for percutaneous sacroiliac screw. The operation duration,intraoperative blood loss,incision length,and postoperative complications (nausea,vomiting,pulmonary infection,wound complications,etc.) were compared between the two groups. The postoperative fracture healing time,postoperative patient satisfaction,and postoperative fractures MATTA scores (to evaluate fracture reduction),postoperative MAJEED function scores,and SF36 scores of the patients were also recorded and compared. No significant differences in baseline characteristics were found between the two groups of patients. All of the patients in both groups had their operations successfully completed. Patients in group B had significantly shorter operations and lower intraoperative blood loss,incision length and postoperative complications than those in group A ( P <0.05). Patients in group B also had higher levels of satisfaction than those in group A ( P <0.05). No significant differences were found between the two groups in postoperative followup time,fracture healing time,postoperative MATTA scores,postoperative MAJEED function scores and SF36 scores ( P >0.05). Sacroiliac joint anterior approach with double reconstruction plate and computer assisted navigation percutaneous sacroiliac screws are both effective for treating Tile C1type pelvic fractures,with similar longterm efficacies. However,computer assisted navigation percutaneous sacroiliac screw has the advantages of less trauma,less bleeding,and quicker.

Continuous Positive Airway Pressure Device Time to Procurement in a Disadvantaged Population.

PubMed

DelRosso, Lourdes M; Hoque, Romy; Chesson, Andrew L

2015-01-01

Introduction. The management of obstructive sleep apnea (OSA) in patients who cannot afford a continuous positive airway pressure (CPAP) device is challenging. In this study we compare time to CPAP procurement in three groups of patients diagnosed with OSA: uninsured subsidized by a humanitarian grant (Group 1), uninsured unsubsidized (Group 2), and those with Medicare or Medicaid (Group 3). We evaluate follow-up and adherence in Group 1. We hypothesize that additional factors, rather than just the ability to obtain CPAP, may uniquely affect follow-up and adherence in uninsured patients. Methods. 30 patients were in Groups 1 and 2, respectively. 12 patients were in Group 3. Time of CPAP procurement from OSA diagnosis to CPAP initiation was assessed in all groups. CPAP adherence data was collected for Group 1 patients at 1, 3, 6, and 9 months. Results. There were no significant differences between groups in gender, age, body mass index, or apnea hypopnea index. The mean time to procurement in Group 1 was shorter compared to Group 2 but not significant. Compared to both Group 1 and Group 2, Group 3 patients had significantly shorter times to device procurement. Conclusion. Time to procurement of CPAP was significantly shorter in those with Medicaid/Medicare insurance compared to the uninsured.

CFD simulation of fatty acid methyl ester production in bubble column reactor

NASA Astrophysics Data System (ADS)

Salleh, N. S. Mohd; Nasir, N. F.

2017-09-01

Non-catalytic transesterification is one of the method that was used to produce the fatty acid methyl ester (FAME) by blowing superheated methanol bubbles continuously into the vegetable oil without using any catalyst. This research aimed to simulate the production of FAME from palm oil in a bubble column reactor. Computational Fluid Dynamic (CFD) simulation was used to predict the distribution of fatty acid methyl ester and other product in the reactor. The fluid flow and component of concentration along the reaction time was investigated and the effects of reaction temperature (523 K and 563 K) on the non-catalytic transesterification process has been examined. The study was carried out using ANSYS CFX 17.1. The finding from the study shows that increasing the temperature leads to higher amount of fatty acid methyl ester can be produced in shorter time. On the other hand, concentration of the component such as triglyceride (TG), glycerol (GL) and fatty acid methyl ester (FAME) can be known when reaching the optimum condition.

The art of spacecraft design: A multidisciplinary challenge

NASA Technical Reports Server (NTRS)

Abdi, F.; Ide, H.; Levine, M.; Austel, L.

1989-01-01

Actual design turn-around time has become shorter due to the use of optimization techniques which have been introduced into the design process. It seems that what, how and when to use these optimization techniques may be the key factor for future aircraft engineering operations. Another important aspect of this technique is that complex physical phenomena can be modeled by a simple mathematical equation. The new powerful multilevel methodology reduces time-consuming analysis significantly while maintaining the coupling effects. This simultaneous analysis method stems from the implicit function theorem and system sensitivity derivatives of input variables. Use of the Taylor's series expansion and finite differencing technique for sensitivity derivatives in each discipline makes this approach unique for screening dominant variables from nondominant variables. In this study, the current Computational Fluid Dynamics (CFD) aerodynamic and sensitivity derivative/optimization techniques are applied for a simple cone-type forebody of a high-speed vehicle configuration to understand basic aerodynamic/structure interaction in a hypersonic flight condition.

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

Mamaluy, Denis; Gao, Xujiao; Tierney, Brian David

We created a highly efficient, universal 3D quant um transport simulator. We demonstrated that the simulator scales linearly - both with the problem size (N) and number of CPUs, which presents an important break-through in the field of computational nanoelectronics. It allowed us, for the first time, to accurately simulate and optim ize a large number of realistic nanodevices in a much shorter time, when compared to other methods/codes such as RGF[%7EN 2.333 ]/KNIT, KWANT, and QTBM[%7EN 3 ]/NEMO5. In order to determine the best-in-class for different beyond-CMOS paradigms, we performed rigorous device optimization for high-performance logic devices at 6-,more » 5- and 4-nm gate lengths. We have discovered that there exists a fundamental down-scaling limit for CMOS technology and other Field-Effect Transistors (FETs). We have found that, at room temperatures, all FETs, irre spective of their channel material, will start experiencing unacceptable level of thermally induced errors around 5-nm gate lengths.« less

A feasible injection molding technique for the manufacturing of large diameter aspheric plastic lenses

NASA Astrophysics Data System (ADS)

Shieh, Jen-Yu; Wang, Luke K.; Ke, Shih-Ying

2010-07-01

A computer aided engineering (CAE) tool-assisted technique, using Moldex3D and aspheric analysis utility (AAU) software in a polycarbonate injection molding design, is proposed to manufacture large diameter aspheric plastic lenses. An experiment is conducted to verify the applicability/feasibility of the proposed technique. Using the preceding two software tools, these crucial process parameters associated with the surface profile errors and birefringence of a molded lens can be attainable. The strategy adopted here is to use the actual quantity of shrinkage after an injection molding trial of an aspherical plastic lens as a reference to perform the core shaping job while keeping the coefficients of aspheric surface, radius, and conic constant unchanged. The design philosophy is characterized by using the CAE tool as a guideline to pursue the best symmetry condition, followed by injection molding trials, to accelerate a product’s developmental time. The advantages are less design complexity and shorter developmental time for a product.

Fast and Efficient Fragment-Based Lead Generation by Fully Automated Processing and Analysis of Ligand-Observed NMR Binding Data.

PubMed

Peng, Chen; Frommlet, Alexandra; Perez, Manuel; Cobas, Carlos; Blechschmidt, Anke; Dominguez, Santiago; Lingel, Andreas

2016-04-14

NMR binding assays are routinely applied in hit finding and validation during early stages of drug discovery, particularly for fragment-based lead generation. To this end, compound libraries are screened by ligand-observed NMR experiments such as STD, T1ρ, and CPMG to identify molecules interacting with a target. The analysis of a high number of complex spectra is performed largely manually and therefore represents a limiting step in hit generation campaigns. Here we report a novel integrated computational procedure that processes and analyzes ligand-observed proton and fluorine NMR binding data in a fully automated fashion. A performance evaluation comparing automated and manual analysis results on (19)F- and (1)H-detected data sets shows that the program delivers robust, high-confidence hit lists in a fraction of the time needed for manual analysis and greatly facilitates visual inspection of the associated NMR spectra. These features enable considerably higher throughput, the assessment of larger libraries, and shorter turn-around times.

Cost-effectiveness analysis of computerized ECG interpretation system in an ambulatory health care organization.

PubMed

Carel, R S

1982-04-01

The cost-effectiveness of a computerized ECG interpretation system in an ambulatory health care organization has been evaluated in comparison with a conventional (manual) system. The automated system was shown to be more cost-effective at a minimum load of 2,500 patients/month. At larger monthly loads an even greater cost-effectiveness was found, the average cost/ECG being about $2. In the manual system the cost/unit is practically independent of patient load. This is primarily due to the fact that 87% of the cost/ECG is attributable to wages and fees of highly trained personnel. In the automated system, on the other hand, the cost/ECG is heavily dependent on examinee load. This is due to the relatively large impact of equipment depreciation on fixed (and total) cost. Utilization of a computer-assisted system leads to marked reduction in cardiologists' interpretation time, substantially shorter turnaround time (of unconfirmed reports), and potential provision of simultaneous service at several remotely located "heart stations."

Vertically inhomogeneous models of the upper crust for the seismoactive region of western Bohemia

NASA Astrophysics Data System (ADS)

Malek, J.; Jansky, J.; Novotny, O.; Rossler, D.

2003-04-01

In the framework of the CELEBRATION 2000 seismic refraction experiment, one international profile crossed the region of earthquake swarms in West-Bohemia/Vogtland. In addition to this main profile, two shorter supplementary profiles and a semicircle were proposed to study the epicentral area in greater detail. Moreover, the shots were also recorded at permanent stations in the region. The observed travel times of the first arrivals are used here to derive vertically inhomogeneous velocity models of the upper crust. After a polynomial or rational smoothing of the observed data, the Wiechert-Herglotz method is used to compute the velocity models. Typical features of the derived models, as opposed to many previous models, are low surface velocities and a prominent velocity increase within the uppermost crust to a depth of about one kilometre. The scatter of observed travel times is discussed in terms of lateral inhomogeneities and anisotropy. In particular, significant differences have been revealed between the Saxothuringian (northern) and adjacent southern parts of the studied area.

Non-extracorporeal circulation for coronary artery bypass graft surgery is more beneficial than extracorporeal circulation.

PubMed

Yang, F-Y; Bao, Y-Z; Liu, F-S; Zhu, Y-C; Zheng, J; Zhang, J-H; Zheng, X-F; Wei, G-C

2015-04-01

The objective of this study was to compare coronary artery bypass graft (CABG) surgery with non-extracorporeal vs. extracorporeal circulation. The study outcomes included operative time, number of graft vessels, pulmonary infection rates, and systemic inflammatory markers. 96 patients received selective CABG, either with non-extracorporeal (study group; n = 48) or extracorporeal circulation (control group; n = 48). Operative time, pulmonary infection rates, and blood levels of inflammatory markers TNF-α, IL-6, and IL-8 before and 4, 24, and 48 hours after the surgery were quantified. Graft vessels were quantified using computed tomography. Operative time was significantly shorter in study group (4.58 ± 0.91 vs. 5.36 ± 1.12 hours in control group; p < 0.05). The number of graft vessels and pulmonary infection rates were comparable between both techniques. However, systemic inflammatory markers were significantly (p < 0.05) lower in study group at 4 and, partly, 24 hours after the surgery. Extracorporeal circulation prolongs operation and can aggravate systemic inflammatory response. Therefore, CABG with non-extracorporeal circulation offers more beneficial outcomes.

Efficacy of Twisted File Adaptive, Reciproc and ProTaper Universal Retreatment instruments for root-canal-filling removal: A cone-beam computed tomography study.

PubMed

Akbulut, Makbule Bilge; Akman, Melek; Terlemez, Arslan; Magat, Guldane; Sener, Sevgi; Shetty, Heeresh

2016-01-01

The aim of this study was to evaluate the efficacy of Twisted File (TF) Adaptive, Reciproc, and ProTaper Universal Retreatment (UR) System instruments for removing root-canal-filling. Sixty single rooted teeth were decoronated, instrumented and obturated. Preoperative CBCT scans were taken and the teeth were retreated with TF Adaptive, Reciproc, ProTaper UR, or hand files (n=15). Then, the teeth were rescanned, and the percentage volume of the residual root-canal-filling material was established. The total time for retreatment was recorded, and the data was statistically analyzed. The statistical ranking of the residual filling material volume was as follows: hand file=TF Adaptive>ProTaper UR=Reciproc. The ProTaper UR and Reciproc systems required shorter periods of time for retreatment. Root canal filling was more efficiently removed by using Reciproc and ProTaper UR instruments than TF Adaptive instruments and hand files. The TF Adaptive system was advantageous over hand files with regard to operating time.

Development and learning of saccadic eye movements in 7- to 42-month-old children.

PubMed

Alahyane, Nadia; Lemoine-Lardennois, Christelle; Tailhefer, Coline; Collins, Thérèse; Fagard, Jacqueline; Doré-Mazars, Karine

2016-01-01

From birth, infants move their eyes to explore their environment, interact with it, and progressively develop a multitude of motor and cognitive abilities. The characteristics and development of oculomotor control in early childhood remain poorly understood today. Here, we examined reaction time and amplitude of saccadic eye movements in 93 7- to 42-month-old children while they oriented toward visual animated cartoon characters appearing at unpredictable locations on a computer screen over 140 trials. Results revealed that saccade performance is immature in children compared to a group of adults: Saccade reaction times were longer, and saccade amplitude relative to target location (10° eccentricity) was shorter. Results also indicated that performance is flexible in children. Although saccade reaction time decreased as age increased, suggesting developmental improvements in saccade control, saccade amplitude gradually improved over trials. Moreover, similar to adults, children were able to modify saccade amplitude based on the visual error made in the previous trial. This second set of results suggests that short visual experience and/or rapid sensorimotor learning are functional in children and can also affect saccade performance.

Anesthetic efficacy of ketamine–diazepam, ketamine–xylazine, and ketamine–acepromazine in Caspian Pond turtles (Mauremys caspica)

PubMed Central

Adel, Milad; Sadegh, Amin Bigham; Arizza, Vincenzo; Abbasi, Hossein; Inguglia, Luigi; Saravi, Hasan Nasrollahzadeh

2017-01-01

Objectives: The objective of this study was to assess the efficacy of different anesthetic drug combinations on the Caspian Pond turtles (Mauremys caspica). Subjects and Methods: Three groups of the Caspian Pond turtles (n = 6) were anesthetized with three different drug combinations. Initially, a pilot study was conducted to determine the best drug doses for the anesthetization of the turtles, and according to these results, ketamine–diazepam (120 mg/kg ketamine hydrochloride [5%] and 2 mg/kg diazepam [5%]), ketamine–acepromazine (120 mg/kg ketamine hydrochloride [5%] and 1 mg/kg acepromazine [1%]), and ketamine–xylazine (120 mg/kg ketamine hydrochloride [5%] and 1 mg/kg xylazine [2%]) were injected intramuscularly. The onset times of anesthetization and the recovery time were measured. Statistical analysis of the data was performed using one-way analysis of variance followed by t-tests, and P < 0.05 was considered statistically significant. Results: There were statistically significant differences in the mean of the onset times of anesthesia and recovery time among the three drug combinations depending on the treatment used. The onset of anesthesia of the animals treated with the ketamine–diazepam combination was 60% and 42% shorter, for male and female turtles, respectively, compared to that obtained with the ketamine–acepromazine combination and 64% (male turtles) and 50% (female turtles) shorter than that obtained with the ketamine–xylazine combination. Further, the recovery time, in male turtles, was 17% shorter in animals treated with the first drug combination than those treated with the ketamine–acepromazine combination and 37% shorter than those treated with the ketamine–xylazine combination. The recovery time, in female turtles, did not seem to be significantly different among treatments. Conclusions: The study showed that the ketamine–diazepam drug combination is the anesthetic combination with the fastest onset time and shortest recovery time. PMID:28458430

77 FR 62191 - Approval and Promulgation of Air Quality Implementation Plans; New Mexico; Infrastructure and...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-12

... such shorter period as EPA may prescribe. Section 110(a)(2) lists the specific infrastructure elements... Act (Act) requires that each state adopt and submit to EPA, within 3 years (or such shorter time... Tailoring Rule because the State does not have the authority to apply the meaning of the term ``subject to...

Reactive nanolaminate pulsed-laser ignition mechanism: Modeling and experimental evidence of diffusion limited reactions

DOE PAGES

Yarrington, C. D.; Abere, M. J.; Adams, D. P.; ...

2017-04-03

We irradiated Al/Pt nanolaminates with a bilayer thickness (tb, width of an Al/Pt pair-layer) of 164 nm with single laser pulses with durations of 10 ms and 0.5 ms at 189 W/cm 2 and 1189 W/cm 2, respectively. The time to ignition was measured for each pulse, and shorter ignition times were observed for the higher power/shorter pulse width. While the shorter pulse shows uniform brightness, videographic images of the irradiated area shortly after ignition show a non-uniform radial brightness for the longer pulse. A diffusion-limited single step reaction mechanism was implemented in a finite element package to model themore » progress from reactants to products at both pulse widths. Finally, the model captures well both the observed ignition delay and qualitative observations regarding the non-uniform radial temperature.« less

Optimization of a shorter variable-acquisition time for legs to achieve true whole-body PET/CT images.

PubMed

Umeda, Takuro; Miwa, Kenta; Murata, Taisuke; Miyaji, Noriaki; Wagatsuma, Kei; Motegi, Kazuki; Terauchi, Takashi; Koizumi, Mitsuru

2017-12-01

The present study aimed to qualitatively and quantitatively evaluate PET images as a function of acquisition time for various leg sizes, and to optimize a shorter variable-acquisition time protocol for legs to achieve better qualitative and quantitative accuracy of true whole-body PET/CT images. The diameters of legs to be modeled as phantoms were defined based on data derived from 53 patients. This study analyzed PET images of a NEMA phantom and three plastic bottle phantoms (diameter, 5.68, 8.54 and 10.7 cm) that simulated the human body and legs, respectively. The phantoms comprised two spheres (diameters, 10 and 17 mm) containing fluorine-18 fluorodeoxyglucose solution with sphere-to-background ratios of 4 at a background radioactivity level of 2.65 kBq/mL. All PET data were reconstructed with acquisition times ranging from 10 to 180, and 1200 s. We visually evaluated image quality and determined the coefficient of variance (CV) of the background, contrast and the quantitative %error of the hot spheres, and then determined two shorter variable-acquisition protocols for legs. Lesion detectability and quantitative accuracy determined based on maximum standardized uptake values (SUV max ) in PET images of a patient using the proposed protocols were also evaluated. A larger phantom and a shorter acquisition time resulted in increased background noise on images and decreased the contrast in hot spheres. A visual score of ≥ 1.5 was obtained when the acquisition time was ≥ 30 s for three leg phantoms, and ≥ 120 s for the NEMA phantom. The quantitative %errors of the 10- and 17-mm spheres in the leg phantoms were ± 15 and ± 10%, respectively, in PET images with a high CV (scan < 30 s). The mean SUV max of three lesions using the current fixed-acquisition and two proposed variable-acquisition time protocols in the clinical study were 3.1, 3.1 and 3.2, respectively, which did not significantly differ. Leg acquisition time per bed position of even 30-90 s allows axial equalization, uniform image noise and a maximum ± 15% quantitative accuracy for the smallest lesion. The overall acquisition time was reduced by 23-42% using the proposed shorter variable than the current fixed-acquisition time for imaging legs, indicating that this is a useful and practical protocol for routine qualitative and quantitative PET/CT assessment in the clinical setting.

[Clinical and radiographic outcomes of navigation-assisted versus conventional total knee arthroplasty].

PubMed

Li, Xiaohui; Yu, Jianhua; Gong, Yuekun; Ren, Kaijing; Liu, Jun

2015-04-21

To assess the early postoperative clinical and radiographic outcomes after navigation-assisted or standard instrumentation total knee arthroplasty (TKA). From August 2007 to May 2008, 60 KSS-A type patients underwent 67 primary TKA operations by the same surgical team. Twenty-two operations were performed with the Image-free navigation system with an average age of 64.5 years while the remaining 45 underwent conventional manual procedures with an average age of 66 years. Their preoperative demographic and functional data had no statistical differences (P>0.05). The operative duration, blood loss volume and hospitalization days were compared for two groups. And radiographic data included coronal femoral component angle, coronal tibial component angle, sagittal femoral component angle, sagittal tibial component angle and coronal tibiofemoral angle after one month. And functional assessment scores were evaluated at 1, 3 and 6 months postoperatively. Operative duration was significantly longer for computer navigation (P<0.05). The average blood loss volume was 555.26 ml in computer navigation group and 647.56 ml in conventional manual method group (P<0.05). And hospitalization stay was shorter in computer navigation group than that in conventional method group (7.74 vs 8.68 days) (P=0.04). The alignment deviation was better in computer-assisted group than that in conventional manual method group (P<0.05). The percentage of patients with a coronal tibiofemoral angle within ±3 of ideal value was 95.45% for computer-assisted mini-invasive TKA group and 80% for conventional TKA group (P=0.003). The Knee Society Clinical Rating Score was higher in computer-assisted group than that in conventional manual method group at 1 and 3 montha post-operation. However, no statistical inter-group difference existed at 6 months post-operation. Navigation allows a surgeon to precisely implant the components for TKA. And it offers faster functional recovery and shorter hospitalization stay. At 6 months post-operation, there is no statistical inter-group difference in KSS scores.

Life history traits in selfing versus outcrossing annuals: exploring the 'time-limitation' hypothesis for the fitness benefit of self-pollination

PubMed Central

Snell, Rebecca; Aarssen, Lonnie W

2005-01-01

Background Most self-pollinating plants are annuals. According to the 'time-limitation' hypothesis, this association between selfing and the annual life cycle has evolved as a consequence of strong r-selection, involving severe time-limitation for completing the life cycle. Under this model, selection from frequent density-independent mortality in ephemeral habitats minimizes time to flower maturation, with selfing as a trade-off, and / or selection minimizes the time between flower maturation and ovule fertilization, in which case selfing has a direct fitness benefit. Predictions arising from this hypothesis were evaluated using phylogenetically-independent contrasts of several life history traits in predominantly selfing versus outcrossing annuals from a data base of 118 species distributed across 14 families. Data for life history traits specifically related to maturation and pollination times were obtained by monitoring the start and completion of different stages of reproductive development in a greenhouse study of selfing and outcrossing annuals from an unbiased sample of 25 species involving five pair-wise family comparisons and four pair-wise genus comparisons. Results Selfing annuals in general had significantly shorter plant heights, smaller flowers, shorter bud development times, shorter flower longevity and smaller seed sizes compared with their outcrossing annual relatives. Age at first flower did not differ significantly between selfing and outcrossing annuals. Conclusions This is the first multi-species study to report these general life-history differences between selfers and outcrossers among annuals exclusively. The results are all explained more parsimoniously by selection associated with time-limitation than by selection associated with pollinator/mate limitation. The shorter bud development time reported here for selfing annuals is predicted explicitly by the time-limitation hypothesis for the fitness benefit of selfing (and not by the alternative 'reproductive assurance' hypothesis associated with pollinator/mate limitation). Support for the time-limitation hypothesis is also evident from published surveys: whereas selfers and outcrossers are about equally represented among annual species as a whole, selfers occur in much higher frequencies among the annual species found in two of the most severely time-limited habitats where flowering plants grow – deserts and cultivated habitats. PMID:15707481

An economic analysis for optimal distributed computing resources for mask synthesis and tape-out in production environment

NASA Astrophysics Data System (ADS)

Cork, Chris; Lugg, Robert; Chacko, Manoj; Levi, Shimon

2005-06-01

With the exponential increase in output database size due to the aggressive optical proximity correction (OPC) and resolution enhancement technique (RET) required for deep sub-wavelength process nodes, the CPU time required for mask tape-out continues to increase significantly. For integrated device manufacturers (IDMs), this can impact the time-to-market for their products where even a few days delay could have a huge commercial impact and loss of market window opportunity. For foundries, a shorter turnaround time provides a competitive advantage in their demanding market, too slow could mean customers looking elsewhere for these services; while a fast turnaround may even command a higher price. With FAB turnaround of a mature, plain-vanilla CMOS process of around 20-30 days, a delay of several days in mask tapeout would contribute a significant fraction to the total time to deliver prototypes. Unlike silicon processing, masks tape-out time can be decreased by simply purchasing extra computing resources and software licenses. Mask tape-out groups are taking advantage of the ever-decreasing hardware cost and increasing power of commodity processors. The significant distributability inherent in some commercial Mask Synthesis software can be leveraged to address this critical business issue. Different implementations have different fractions of the code that cannot be parallelized and this affects the efficiency with which it scales, as is described by Amdahl"s law. Very few are efficient enough to allow the effective use of 1000"s of processors, enabling run times to drop from days to only minutes. What follows is a cost aware methodology to quantify the scalability of this class of software, and thus act as a guide to estimating the optimal investment in terms of hardware and software licenses.

Factors influencing the latency of simple reaction time

PubMed Central

Woods, David L.; Wyma, John M.; Yund, E. William; Herron, Timothy J.; Reed, Bruce

2015-01-01

Simple reaction time (SRT), the minimal time needed to respond to a stimulus, is a basic measure of processing speed. SRTs were first measured by Francis Galton in the 19th century, who reported visual SRT latencies below 190 ms in young subjects. However, recent large-scale studies have reported substantially increased SRT latencies that differ markedly in different laboratories, in part due to timing delays introduced by the computer hardware and software used for SRT measurement. We developed a calibrated and temporally precise SRT test to analyze the factors that influence SRT latencies in a paradigm where visual stimuli were presented to the left or right hemifield at varying stimulus onset asynchronies (SOAs). Experiment 1 examined a community sample of 1469 subjects ranging in age from 18 to 65. Mean SRT latencies were short (231, 213 ms when corrected for hardware delays) and increased significantly with age (0.55 ms/year), but were unaffected by sex or education. As in previous studies, SRTs were prolonged at shorter SOAs and were slightly faster for stimuli presented in the visual field contralateral to the responding hand. Stimulus detection time (SDT) was estimated by subtracting movement initiation time, measured in a speeded finger tapping test, from SRTs. SDT latencies averaged 131 ms and were unaffected by age. Experiment 2 tested 189 subjects ranging in age from 18 to 82 years in a different laboratory using a larger range of SOAs. Both SRTs and SDTs were slightly prolonged (by 7 ms). SRT latencies increased with age while SDT latencies remained stable. Precise computer-based measurements of SRT latencies show that processing speed is as fast in contemporary populations as in the Victorian era, and that age-related increases in SRT latencies are due primarily to slowed motor output. PMID:25859198

Sample Size for Measuring Grammaticality in Preschool Children from Picture-Elicited Language Samples

ERIC Educational Resources Information Center

Eisenberg, Sarita L.; Guo, Ling-Yu

2015-01-01

Purpose: The purpose of this study was to investigate whether a shorter language sample elicited with fewer pictures (i.e., 7) would yield a percent grammatical utterances (PGU) score similar to that computed from a longer language sample elicited with 15 pictures for 3-year-old children. Method: Language samples were elicited by asking forty…

Predicting drug hydrolysis based on moisture uptake in various packaging designs.

PubMed

Naversnik, Klemen; Bohanec, Simona

2008-12-18

An attempt was made to predict the stability of a moisture sensitive drug product based on the knowledge of the dependence of the degradation rate on tablet moisture. The moisture increase inside a HDPE bottle with the drug formulation was simulated with the sorption-desorption moisture transfer model, which, in turn, allowed an accurate prediction of the drug degradation kinetics. The stability prediction, obtained by computer simulation, was made in a considerably shorter time frame and required little resources compared to a conventional stability study. The prediction was finally upgraded to a stochastic Monte Carlo simulation, which allowed quantitative incorporation of uncertainty, stemming from various sources. The resulting distribution of the outcome of interest (amount of degradation product at expiry) is a comprehensive way of communicating the result along with its uncertainty, superior to single-value results or confidence intervals.

A Virtual Hosting Environment for Distributed Online Gaming

NASA Astrophysics Data System (ADS)

Brossard, David; Prieto Martinez, Juan Luis

With enterprise boundaries becoming fuzzier, it’s become clear that businesses need to share resources, expose services, and interact in many different ways. In order to achieve such a distribution in a dynamic, flexible, and secure way, we have designed and implemented a virtual hosting environment (VHE) which aims at integrating business services across enterprise boundaries and virtualising the ICT environment within which these services operate in order to exploit economies of scale for the businesses as well as achieve shorter concept-to-market time scales. To illustrate the relevance of the VHE, we have applied it to the online gaming world. Online gaming is an early adopter of distributed computing and more than 30% of gaming developer companies, being aware of the shift, are focusing on developing high performance platforms for the new online trend.

Three-dimensional particle tracking velocimetry algorithm based on tetrahedron vote

NASA Astrophysics Data System (ADS)

Cui, Yutong; Zhang, Yang; Jia, Pan; Wang, Yuan; Huang, Jingcong; Cui, Junlei; Lai, Wing T.

2018-02-01

A particle tracking velocimetry algorithm based on tetrahedron vote, which is named TV-PTV, is proposed to overcome the limited selection problem of effective algorithms for 3D flow visualisation. In this new cluster-matching algorithm, tetrahedrons produced by the Delaunay tessellation are used as the basic units for inter-frame matching, which results in a simple algorithmic structure of only two independent preset parameters. Test results obtained using the synthetic test image data from the Visualisation Society of Japan show that TV-PTV presents accuracy comparable to that of the classical algorithm based on new relaxation method (NRX). Compared with NRX, TV-PTV possesses a smaller number of loops in programming and thus a shorter computing time, especially for large particle displacements and high particle concentration. TV-PTV is confirmed practically effective using an actual 3D wake flow.

Photogrammetry of fetal breathing movements during the third trimester of pregnancy: observations in normal and abnormal pregnancies.

PubMed

Florido, J; Padilla, M C; Soto, V; Camacho, A; Moscoso, G; Navarrete, L

2008-09-01

To evaluate parameters of fetal breathing movements-displacement of the fetal abdominal wall during inspiration and expiration, time of inspiration and expiration and speed of inspiration and expiration-between 30 and 36 weeks' gestation in normal pregnancies, and in those complicated by gestational diabetes or maternal hypertension. Three categories of pregnancy were investigated: 49 were normal, 16 had pregnancy-induced diabetes and 10 were hypertensive. According to their gestational age, the patients were divided into two groups: Group A between 30 and 32 weeks' gestation and Group B between 33 and 36 weeks. Using photogrammetry and a computer-operated algorithm, six parameters of fetal breathing movements were investigated. There were significant differences in the various fetal parameters measured among the three categories of pregnant women. Up until 32 weeks of gestation, the displacements during inspiration and expiration were larger, the speeds of inspiration and expiration were higher, and the times for inspiration and expiration were shorter in the diabetic and hypertensive groups than in the normal group. In the later period, between 33 and 36 weeks, fetuses of pregnancy-induced diabetic patients showed the lowest inspiration and expiration times and the highest speeds of inspiration and expiration. Photogrammetry in conjunction with a computer-operated algorithm can be used to assess fetal breathing movements. There are significant differences in fetal breathing movements between normal pregnancies and those that are complicated by gestational diabetes or hypertension.

Postoperative Stereotactic Radiosurgery Without Whole-Brain Radiation Therapy for Brain Metastases: Potential Role of Preoperative Tumor Size

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

Hartford, Alan C., E-mail: Alan.C.Hartford@Hitchcock.org; Paravati, Anthony J.; Spire, William J.

2013-03-01

Purpose: Radiation therapy following resection of a brain metastasis increases the probability of disease control at the surgical site. We analyzed our experience with postoperative stereotactic radiosurgery (SRS) as an alternative to whole-brain radiotherapy (WBRT), with an emphasis on identifying factors that might predict intracranial disease control and overall survival (OS). Methods and Materials: We retrospectively reviewed all patients through December 2008, who, after surgical resection, underwent SRS to the tumor bed, deferring WBRT. Multiple factors were analyzed for time to intracranial recurrence (ICR), whether local recurrence (LR) at the surgical bed or “distant” recurrence (DR) in the brain, formore » time to WBRT, and for OS. Results: A total of 49 lesions in 47 patients were treated with postoperative SRS. With median follow-up of 9.3 months (range, 1.1-61.4 months), local control rates at the resection cavity were 85.5% at 1 year and 66.9% at 2 years. OS rates at 1 and 2 years were 52.5% and 31.7%, respectively. On univariate analysis (preoperative) tumors larger than 3.0 cm exhibited a significantly shorter time to LR. At a cutoff of 2.0 cm, larger tumors resulted in significantly shorter times not only for LR but also for DR, ICR, and salvage WBRT. While multivariate Cox regressions showed preoperative size to be significant for times to DR, ICR, and WBRT, in similar multivariate analysis for OS, only the graded prognostic assessment proved to be significant. However, the number of intracranial metastases at presentation was not significantly associated with OS nor with other outcome variables. Conclusions: Larger tumor size was associated with shorter time to recurrence and with shorter time to salvage WBRT; however, larger tumors were not associated with decrements in OS, suggesting successful salvage. SRS to the tumor bed without WBRT is an effective treatment for resected brain metastases, achieving local control particularly for tumors up to 3.0 cm diameter.« less

Electronic mail was not better than postal mail for surveying residents and faculty.

PubMed

Akl, Elie A; Maroun, Nancy; Klocke, Robert A; Montori, Victor; Schünemann, Holger J

2005-04-01

To compare response rate, time to response, and data quality of electronic and postal surveys in the setting of postgraduate medical education. A randomized controlled trial in a university-based internal medicine residency program. We randomized 119 residents and 83 faculty to an electronic versus a postal survey with up to two reminders and measured response rate, time to response, and data quality. For residents, the e-survey resulted in a lower response rate than the postal survey (63.3% versus 79.7%; difference -16.3%, 95% confidence interval (95% CI) -32.3% to -0.4%%; P=.049), but a shorter mean response time, by 3.8 days (95% CI 0.2-7.4; P=.042). For faculty, the e-survey did not result in a significantly lower response rate than the postal survey (85.4% vs. 81.0%; difference 4.4%, 95% CI -11.7 to 20.5%; P=.591), but resulted in a shorter average response time, by 8.4 days (95% CI 4.4 to 12.4; P < 0.001). There were no differences in the quality of data or responses to the survey between the two methods. E-surveys were not superior to postal surveys in terms of response rate, but resulted in shorter time to response and equivalent data quality.

Gelatin-thrombin hemostatic matrix in neurosurgical procedures: hemostasis effectiveness and economic value of clinical and surgical procedure-related benefits.

PubMed

Esposito, Felice; Cappabianca, Paolo; Angileri, Filippo F; Cavallo, Luigi M; Priola, Stefano M; Crimi, Salvatore; Solari, Domenico; Germanò, Antonino F; Tomasello, Francesco

2016-07-26

Gelatin-thrombin hemostatic matrix (FloSeal®) use is associated with shorter surgical times and less blood loss, parameters that are highly valued in neurosurgical procedures. We aimed to assess the effectiveness of gelatin-thrombin in neurosurgical procedures and estimate its economic value. In a 6-month retrospective evaluation at 2 hospitals, intraoperative and postoperative information were collected from patients undergoing neurosurgical procedures where bleeding was controlled with gelatin-thrombin matrix or according to local bleeding control guidelines (control group). Study endpoints were: length of surgery, estimated blood loss, hospitalization duration, blood units utilized, intensive care unit days, postoperative complications, and time-to-recovery. Statistical methods compared endpoints between the gelatin-thrombin and control groups and resource utilization costs were estimated. Seventy-eight patients (38 gelatin-thrombin; 40 control) were included. Gelatin-thrombin was associated with a shorter surgery duration than control 166±40 versus 185±55, p=0.0839); a lower estimated blood loss (185±80 versus 250±95ml; p=0.0017); a shorter hospital stay (10±3 versus 13±3 days; p<0.001); fewer intensive care unit days (10 days/3 patients and 20 days/4 patients); and shorter time-to-recovery (3±2.2 versus 4±2.8 weeks; p=0861). Fewer gelatin-thrombin patients experienced postoperative complications (3 minor) than the control group (5 minor; 3 major). No gelatin-thrombin patient required blood transfusion; 5 units were administered in the control group. The cost of gelatin-thrombin (€268.40/unit) was offset by the shorter surgery duration (difference of 19 minutes at €858 per hour) and the economic value of improved the other endpoint outcomes (ie, shorter hospital stay, less blood loss/lack of need for transfusion, fewer intensive care unit days, and complications). Gelatin-thrombin hemostatic matrix use in patients undergoing neurosurgical procedures was associated with better intra- and post-operative parameters than conventional hemostasis methods, with these parameters having substantial economic benefits.

Aztec arithmetic revisited: land-area algorithms and Acolhua congruence arithmetic.

PubMed

Williams, Barbara J; Jorge y Jorge, María del Carmen

2008-04-04

Acolhua-Aztec land records depicting areas and side dimensions of agricultural fields provide insight into Aztec arithmetic. Hypothesizing that recorded areas resulted from indigenous calculation, in a study of sample quadrilateral fields we found that 60% of the area values could be reproduced exactly by computation. In remaining cases, discrepancies between computed and recorded areas were consistently small, suggesting use of an unknown indigenous arithmetic. In revisiting the research, we discovered evidence for the use of congruence principles, based on proportions between the standard linear Acolhua measure and their units of shorter length. This procedure substitutes for computation with fractions and is labeled "Acolhua congruence arithmetic." The findings also clarify variance between Acolhua and Tenochca linear units, long an issue in understanding Aztec metrology.

Effect of correlated decay on fault-tolerant quantum computation

NASA Astrophysics Data System (ADS)

Lemberger, B.; Yavuz, D. D.

2017-12-01

We analyze noise in the circuit model of quantum computers when the qubits are coupled to a common bosonic bath and discuss the possible failure of scalability of quantum computation. Specifically, we investigate correlated (super-radiant) decay between the qubit energy levels from a two- or three-dimensional array of qubits without imposing any restrictions on the size of the sample. We first show that regardless of how the spacing between the qubits compares with the emission wavelength, correlated decay produces errors outside the applicability of the threshold theorem. This is because the sum of the norms of the two-body interaction Hamiltonians (which can be viewed as the upper bound on the single-qubit error) that decoheres each qubit scales with the total number of qubits and is unbounded. We then discuss two related results: (1) We show that the actual error (instead of the upper bound) on each qubit scales with the number of qubits. As a result, in the limit of large number of qubits in the computer, N →∞ , correlated decay causes each qubit in the computer to decohere in ever shorter time scales. (2) We find the complete eigenvalue spectrum of the exchange Hamiltonian that causes correlated decay in the same limit. We show that the spread of the eigenvalue distribution grows faster with N compared to the spectrum of the unperturbed system Hamiltonian. As a result, as N →∞ , quantum evolution becomes completely dominated by the noise due to correlated decay. These results argue that scalable quantum computing may not be possible in the circuit model in a two- or three- dimensional geometry when the qubits are coupled to a common bosonic bath.

Confidence intervals for the between-study variance in random-effects meta-analysis using generalised heterogeneity statistics: should we use unequal tails?

PubMed

Jackson, Dan; Bowden, Jack

2016-09-07

Confidence intervals for the between study variance are useful in random-effects meta-analyses because they quantify the uncertainty in the corresponding point estimates. Methods for calculating these confidence intervals have been developed that are based on inverting hypothesis tests using generalised heterogeneity statistics. Whilst, under the random effects model, these new methods furnish confidence intervals with the correct coverage, the resulting intervals are usually very wide, making them uninformative. We discuss a simple strategy for obtaining 95 % confidence intervals for the between-study variance with a markedly reduced width, whilst retaining the nominal coverage probability. Specifically, we consider the possibility of using methods based on generalised heterogeneity statistics with unequal tail probabilities, where the tail probability used to compute the upper bound is greater than 2.5 %. This idea is assessed using four real examples and a variety of simulation studies. Supporting analytical results are also obtained. Our results provide evidence that using unequal tail probabilities can result in shorter 95 % confidence intervals for the between-study variance. We also show some further results for a real example that illustrates how shorter confidence intervals for the between-study variance can be useful when performing sensitivity analyses for the average effect, which is usually the parameter of primary interest. We conclude that using unequal tail probabilities when computing 95 % confidence intervals for the between-study variance, when using methods based on generalised heterogeneity statistics, can result in shorter confidence intervals. We suggest that those who find the case for using unequal tail probabilities convincing should use the '1-4 % split', where greater tail probability is allocated to the upper confidence bound. The 'width-optimal' interval that we present deserves further investigation.

Application of Adjoint Method and Spectral-Element Method to Tomographic Inversion of Regional Seismological Structure Beneath Japanese Islands

NASA Astrophysics Data System (ADS)

Tsuboi, S.; Miyoshi, T.; Obayashi, M.; Tono, Y.; Ando, K.

2014-12-01

Recent progress in large scale computing by using waveform modeling technique and high performance computing facility has demonstrated possibilities to perform full-waveform inversion of three dimensional (3D) seismological structure inside the Earth. We apply the adjoint method (Liu and Tromp, 2006) to obtain 3D structure beneath Japanese Islands. First we implemented Spectral-Element Method to K-computer in Kobe, Japan. We have optimized SPECFEM3D_GLOBE (Komatitsch and Tromp, 2002) by using OpenMP so that the code fits hybrid architecture of K-computer. Now we could use 82,134 nodes of K-computer (657,072 cores) to compute synthetic waveform with about 1 sec accuracy for realistic 3D Earth model and its performance was 1.2 PFLOPS. We use this optimized SPECFEM3D_GLOBE code and take one chunk around Japanese Islands from global mesh and compute synthetic seismograms with accuracy of about 10 second. We use GAP-P2 mantle tomography model (Obayashi et al., 2009) as an initial 3D model and use as many broadband seismic stations available in this region as possible to perform inversion. We then use the time windows for body waves and surface waves to compute adjoint sources and calculate adjoint kernels for seismic structure. We have performed several iteration and obtained improved 3D structure beneath Japanese Islands. The result demonstrates that waveform misfits between observed and theoretical seismograms improves as the iteration proceeds. We now prepare to use much shorter period in our synthetic waveform computation and try to obtain seismic structure for basin scale model, such as Kanto basin, where there are dense seismic network and high seismic activity. Acknowledgements: This research was partly supported by MEXT Strategic Program for Innovative Research. We used F-net seismograms of the National Research Institute for Earth Science and Disaster Prevention.

Incidental renal tumours on low-dose CT lung cancer screening exams.

PubMed

Pinsky, Paul F; Dunn, Barbara; Gierada, David; Nath, P Hrudaya; Munden, Reginald; Berland, Lincoln; Kramer, Barnett S

2017-06-01

Introduction Renal cancer incidence has increased markedly in the United States in recent decades, largely due to incidentally detected tumours from computed tomography imaging. Here, we analyze the potential for low-dose computed tomography lung cancer screening to detect renal cancer. Methods The National Lung Screening Trial randomized subjects to three annual screens with either low-dose computed tomography or chest X-ray. Eligibility criteria included 30 + pack-years, current smoking or quit within 15 years, and age 55-74. Subjects were followed for seven years. Low-dose computed tomography screening forms collected information on lung cancer and non-lung cancer abnormalities, including abnormalities below the diaphragm. A reader study was performed on a sample of National Lung Screening Trial low-dose computed tomography images assessing presence of abnormalities below the diaphragms and abnormalities suspicious for renal cancer. Results There were 26,722 and 26,732 subjects enrolled in the low-dose computed tomography and chest X-ray arms, respectively, and there were 104 and 85 renal cancer cases diagnosed, respectively (relative risk = 1.22, 95% CI: 0.9-1.5). From 75,126 low-dose computed tomography screens, there were 46 renal cancer diagnoses within one year. Abnormalities below the diaphragm rates were 39.1% in screens with renal cancer versus 4.1% in screens without (P < 0.001). Cases with abnormalities below the diaphragms had shorter median time to diagnosis than those without (71 vs. 160 days, P = 0.004). In the reader study, 64% of renal cancer cases versus 13% of non-cases had abnormalities below the diaphragms; 55% of cases and 0.8% of non-cases had a finding suspicious for renal cancer (P < 0.001). Conclusion Low-dose computed tomography screens can potentially detect renal cancers. The benefits to harms tradeoff of incidental detection of renal tumours on low-dose computed tomography is unknown.

Low-dose x-ray tomography through a deep convolutional neural network

DOE PAGES

Yang, Xiaogang; De Andrade, Vincent; Scullin, William; ...

2018-02-07

Synchrotron-based X-ray tomography offers the potential of rapid large-scale reconstructions of the interiors of materials and biological tissue at fine resolution. However, for radiation sensitive samples, there remain fundamental trade-offs between damaging samples during longer acquisition times and reducing signals with shorter acquisition times. We present a deep convolutional neural network (CNN) method that increases the acquired X-ray tomographic signal by at least a factor of 10 during low-dose fast acquisition by improving the quality of recorded projections. Short exposure time projections enhanced with CNN show similar signal to noise ratios as compared with long exposure time projections and muchmore » lower noise and more structural information than low-dose fats acquisition without CNN. We optimized this approach using simulated samples and further validated on experimental nano-computed tomography data of radiation sensitive mouse brains acquired with a transmission X-ray microscopy. We demonstrate that automated algorithms can reliably trace brain structures in datasets collected with low dose-CNN. As a result, this method can be applied to other tomographic or scanning based X-ray imaging techniques and has great potential for studying faster dynamics in specimens.« less

Parallel methodology to capture cyclic variability in motored engines

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

Ameen, Muhsin M.; Yang, Xiaofeng; Kuo, Tang-Wei

2016-07-28

Numerical prediction of of cycle-to-cycle variability (CCV) in SI engines is extremely challenging for two key reasons: (i) high-fidelity methods such as large eddy simulation (LES) are require to accurately capture the in-cylinder turbulent flowfield, and (ii) CCV is experienced over long timescales and hence the simulations need to be performed for hundreds of consecutive cycles. In this study, a new methodology is proposed to dissociate this long time-scale problem into several shorter time-scale problems, which can considerably reduce the computational time without sacrificing the fidelity of the simulations. The strategy is to perform multiple single-cycle simulations in parallel bymore » effectively perturbing the simulation parameters such as the initial and boundary conditions. It is shown that by perturbing the initial velocity field effectively based on the intensity of the in-cylinder turbulence, the mean and variance of the in-cylinder flowfield is captured reasonably well. Adding perturbations in the initial pressure field and the boundary pressure improves the predictions. It is shown that this new approach is able to give accurate predictions of the flowfield statistics in less than one-tenth of time required for the conventional approach of simulating consecutive engine cycles.« less

An all-optronic synthetic aperture lidar

NASA Astrophysics Data System (ADS)

Turbide, Simon; Marchese, Linda; Terroux, Marc; Babin, François; Bergeron, Alain

2012-09-01

Synthetic Aperture Radar (SAR) is a mature technology that overcomes the diffraction limit of an imaging system's real aperture by taking advantage of the platform motion to coherently sample multiple sections of an aperture much larger than the physical one. Synthetic Aperture Lidar (SAL) is the extension of SAR to much shorter wavelengths (1.5 μm vs 5 cm). This new technology can offer higher resolution images in day or night time as well as in certain adverse conditions. It could be a powerful tool for Earth monitoring (ship detection, frontier surveillance, ocean monitoring) from aircraft, unattended aerial vehicle (UAV) or spatial platforms. A continuous flow of high-resolution images covering large areas would however produce a large amount of data involving a high cost in term of post-processing computational time. This paper presents a laboratory demonstration of a SAL system complete with image reconstruction based on optronic processing. This differs from the more traditional digital approach by its real-time processing capability. The SAL system is discussed and images obtained from a non-metallic diffuse target at ranges up to 3m are shown, these images being processed by a real-time optronic SAR processor origiinally designed to reconstruct SAR images from ENVISAT/ASAR data.

Low-dose x-ray tomography through a deep convolutional neural network

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

Yang, Xiaogang; De Andrade, Vincent; Scullin, William

Synchrotron-based X-ray tomography offers the potential of rapid large-scale reconstructions of the interiors of materials and biological tissue at fine resolution. However, for radiation sensitive samples, there remain fundamental trade-offs between damaging samples during longer acquisition times and reducing signals with shorter acquisition times. We present a deep convolutional neural network (CNN) method that increases the acquired X-ray tomographic signal by at least a factor of 10 during low-dose fast acquisition by improving the quality of recorded projections. Short exposure time projections enhanced with CNN show similar signal to noise ratios as compared with long exposure time projections and muchmore » lower noise and more structural information than low-dose fats acquisition without CNN. We optimized this approach using simulated samples and further validated on experimental nano-computed tomography data of radiation sensitive mouse brains acquired with a transmission X-ray microscopy. We demonstrate that automated algorithms can reliably trace brain structures in datasets collected with low dose-CNN. As a result, this method can be applied to other tomographic or scanning based X-ray imaging techniques and has great potential for studying faster dynamics in specimens.« less

Simultaneous multislice refocusing via time optimal control.

PubMed

Rund, Armin; Aigner, Christoph Stefan; Kunisch, Karl; Stollberger, Rudolf

2018-02-09

Joint design of minimum duration RF pulses and slice-selective gradient shapes for MRI via time optimal control with strict physical constraints, and its application to simultaneous multislice imaging. The minimization of the pulse duration is cast as a time optimal control problem with inequality constraints describing the refocusing quality and physical constraints. It is solved with a bilevel method, where the pulse length is minimized in the upper level, and the constraints are satisfied in the lower level. To address the inherent nonconvexity of the optimization problem, the upper level is enhanced with new heuristics for finding a near global optimizer based on a second optimization problem. A large set of optimized examples shows an average temporal reduction of 87.1% for double diffusion and 74% for turbo spin echo pulses compared to power independent number of slices pulses. The optimized results are validated on a 3T scanner with phantom measurements. The presented design method computes minimum duration RF pulse and slice-selective gradient shapes subject to physical constraints. The shorter pulse duration can be used to decrease the effective echo time in existing echo-planar imaging or echo spacing in turbo spin echo sequences. © 2018 International Society for Magnetic Resonance in Medicine.

Hemodialysis

MedlinePlus

... center, hemodialysis is usually done 3 times per week for about 4 hours at a time. People who choose to do ... at home may do dialysis treatment more frequently, 4-7 times per week for shorter hours each time. Your doctor will give you a ...

Sleep problems and computer use during work and leisure: Cross-sectional study among 7800 adults.

PubMed

Andersen, Lars Louis; Garde, Anne Helene

2015-01-01

Previous studies linked heavy computer use to disturbed sleep. This study investigates the association between computer use during work and leisure and sleep problems in working adults. From the 2010 round of the Danish Work Environment Cohort Study, currently employed wage earners on daytime schedule (N = 7883) replied to the Bergen insomnia scale and questions on weekly duration of computer use. Results showed that sleep problems for three or more days per week (average of six questions) were experienced by 14.9% of the respondents. Logistic regression analyses, controlled for gender, age, physical and psychosocial work factors, lifestyle, chronic disease and mental health showed that computer use during leisure for 30 or more hours per week (reference 0-10 hours per week) was associated with increased odds of sleep problems (OR 1.83 [95% CI 1.06-3.17]). Computer use during work and shorter duration of computer use during leisure were not associated with sleep problems. In conclusion, excessive computer use during leisure - but not work - is associated with sleep problems in adults working on daytime schedule.

Does Foot Anthropometry Predict Metabolic Cost During Running?

PubMed

van Werkhoven, Herman; Piazza, Stephen J

2017-10-01

Several recent investigations have linked running economy to heel length, with shorter heels being associated with less metabolic energy consumption. It has been hypothesized that shorter heels require larger plantar flexor muscle forces, thus increasing tendon energy storage and reducing metabolic cost. The goal of this study was to investigate this possible mechanism for metabolic cost reduction. Fifteen male subjects ran at 16 km⋅h -1 on a treadmill and subsequently on a force-plate instrumented runway. Measurements of oxygen consumption, kinematics, and ground reaction forces were collected. Correlational analyses were performed between oxygen consumption and anthropometric and kinetic variables associated with the ankle and foot. Correlations were also computed between kinetic variables (peak joint moment and peak tendon force) and heel length. Estimated peak Achilles tendon force normalized to body weight was found to be strongly correlated with heel length normalized to body height (r = -.751, p = .003). Neither heel length nor any other measured or calculated variable were correlated with oxygen consumption, however. Subjects with shorter heels experienced larger Achilles tendon forces, but these forces were not associated with reduced metabolic cost. No other anthropometric and kinetic variables considered explained the variance in metabolic cost across individuals.

Beyond Access and Exposure: Implications of Sneaky Media Use for Preschoolers' Sleep Behavior.

PubMed

Moorman, Jessica D; Harrison, Kristen

2018-01-09

Greater consumption of and access to screen media are known correlates of unhealthy sleep behavior in preschoolers. What remains unknown, however, is the role a child's media use plays in this association. Parents and guardians of U.S. preschoolers (N = 278, average child age 56 months) provided information about their child's nightly duration of sleep, daily duration of nap, quantity of screen media use, sneaky media use, and the presence of a screen media device in the bedroom. We assessed four media: television, DVD/VCRs, video games, and computer/Internet. Based on rationales of sleep displacement, the forbidden fruit hypothesis, and social cognitive theory, we predicted that increased consumption of and access to media, along with sneaky media use, would predict a shorter duration of nightly sleep and longer duration of daily nap across the four screen media. In correlational analyses, a clear pattern emerged with quantity of media use, screen media in the bedroom, and sneaky media use associated with shorter nightly duration of sleep and longer duration of daily nap. In regression analyses, only weekday evening television viewing and sneaky media use predicted shorter nightly sleep duration; weekend morning and evening DVD use predicted longer naps.

Predictors of lapse in first week of smoking abstinence in PTSD and non-PTSD smokers.

PubMed

Beckham, Jean C; Calhoun, Patrick S; Dennis, Michelle F; Wilson, Sarah M; Dedert, Eric A

2013-06-01

Retrospective research suggests smokers with posttraumatic stress disorder (PTSD) lapse more quickly after their quit date. Ecological momentary assessment (EMA) research is needed to confirm the presence of early smoking lapse in PTSD and form conceptualizations that inform intervention. Smokers with (n = 55) and without (n = 52) PTSD completed alarm-prompted EMA of situational and psychiatric variables the week before and after a quit date, and self-initiated EMA following smoking lapses. Blood samples at baseline and on the quit date allowed assessment of dehydroepiandrosterone (DHEA) and dehydroepiandrosterone sulfate (DHEA(S)). PTSD was related to shorter time to lapse (hazard ratio [HR] = 1.677, 95% CI: 1.106-2.544). Increased smoking abstinence self-efficacy was related to longer time to lapse (HR = 0.608, 95% CI: 0.430-0.860). Analyses of participants' real-time reports revealed that smokers with PTSD were more likely to attribute first-time lapses to negative affect ( = 5.412, p = .020), and trauma reminders (Fisher's exact p = .003**). Finally, the quit date decrease in DHEA(S) was related to shorter time to lapse (HR = 1.009, 95% CI: 1.000-1.018, p < .05). Results provide evidence of shorter time to first smoking lapse in PTSD, and add to evidence that early lapse occasions are more strongly related to trauma reminders, negative affect, and cravings in smokers with PTSD.

Retention time alignment of LC/MS data by a divide-and-conquer algorithm.

PubMed

Zhang, Zhongqi

2012-04-01

Liquid chromatography-mass spectrometry (LC/MS) has become the method of choice for characterizing complex mixtures. These analyses often involve quantitative comparison of components in multiple samples. To achieve automated sample comparison, the components of interest must be detected and identified, and their retention times aligned and peak areas calculated. This article describes a simple pairwise iterative retention time alignment algorithm, based on the divide-and-conquer approach, for alignment of ion features detected in LC/MS experiments. In this iterative algorithm, ion features in the sample run are first aligned with features in the reference run by applying a single constant shift of retention time. The sample chromatogram is then divided into two shorter chromatograms, which are aligned to the reference chromatogram the same way. Each shorter chromatogram is further divided into even shorter chromatograms. This process continues until each chromatogram is sufficiently narrow so that ion features within it have a similar retention time shift. In six pairwise LC/MS alignment examples containing a total of 6507 confirmed true corresponding feature pairs with retention time shifts up to five peak widths, the algorithm successfully aligned these features with an error rate of 0.2%. The alignment algorithm is demonstrated to be fast, robust, fully automatic, and superior to other algorithms. After alignment and gap-filling of detected ion features, their abundances can be tabulated for direct comparison between samples.

Sutureless versus Conventional Aortic Valve Replacement: Outcomes in 70 High-Risk Patients Undergoing Concomitant Cardiac Procedures.

PubMed

Hanedan, Muhammet Onur; Yuruk, Mehmet Ali; Parlar, Ali Ihsan; Ziyrek, Ugur; Arslan, Ali Kemal; Sayar, Ufuk; Mataraci, Ilker

2018-02-01

In elderly, high-risk surgical patients, sutureless aortic valve replacement (AVR) can often be an alternative to conventional AVR; shorter aortic cross-clamp and cardiopulmonary bypass times are the chief advantages. We compared the outcomes of sutureless AVR with those of conventional AVR in 70 elderly patients who underwent concomitant cardiac surgical procedures. We retrospectively analyzed the cases of 42 men and 28 women (mean age, 70.4 ± 10.3 yr; range, 34-93 yr) who underwent cardiac operations plus AVR with either a sutureless valve (group 1, n=38) or a conventional bioprosthetic or mechanical valve (group 2, n=32). Baseline patient characteristics were similar except for worse New York Heart Association functional status and the prevalence of diabetes mellitus in group 1. In group 1, the operative, cross-clamp, and cardiopulmonary bypass times were shorter (all P =0.001), postoperative drainage amounts were lower ( P =0.009), hospital stays were shorter ( P =0.004), and less red blood cell transfusion was needed ( P =0.037). Echocardiograms before patients' discharge from the hospital showed lower peak and mean aortic gradients in group 1 (mean transvalvular gradient, 8.4 ± 2.8 vs 12.2 ± 5.2 mmHg; P =0.012). We found that elderly, high-risk patients who underwent multiple cardiac surgical procedures and sutureless AVR had better hemodynamic outcomes and shorter ischemic times than did patients who underwent conventional AVR.

Concurrent schedules of wheel-running reinforcement: choice between different durations of opportunity to run in rats.

PubMed

Belke, Terry W

2006-02-01

How do animals choose between opportunities to run of different durations? Are longer durations preferred over shorter durations because they permit a greater number of revolutions? Are shorter durations preferred because they engender higher rates of running? Will longer durations be chosen because running is less constrained? The present study reports on three experiments that attempted to address these questions. In the first experiment, five male Wistar rats chose between 10-sec and 50-sec opportunities to run on modified concurrent variable-interval (VI) schedules. Across conditions, the durations associated with the alternatives were reversed. Response, time, and reinforcer proportions did not vary from indifference. In a second experiment, eight female Long-Evans rats chose between opportunities to run of equal (30 sec) and unequal durations (10 sec and 50 sec) on concurrent variable-ratio (VR) schedules. As in Experiment 1, between presentations of equal duration conditions, 10-sec and 50-sec durations were reversed. Results showed that response, time, and reinforcer proportions on an alternative did not vary with reinforcer duration. In a third experiment, using concurrent VR schedules, durations were systematically varied to decrease the shorter duration toward 0 sec. As the shorter duration decreased, response, time, and reinforcer proportions shifted toward the longer duration. In summary, differences in durations of opportunities to run did not affect choice behavior in a manner consistent with the assumption that a longer reinforcer is a larger reinforcer.

Sub-Second Parallel State Estimation

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

Chen, Yousu; Rice, Mark J.; Glaesemann, Kurt R.

This report describes the performance of Pacific Northwest National Laboratory (PNNL) sub-second parallel state estimation (PSE) tool using the utility data from the Bonneville Power Administrative (BPA) and discusses the benefits of the fast computational speed for power system applications. The test data were provided by BPA. They are two-days’ worth of hourly snapshots that include power system data and measurement sets in a commercial tool format. These data are extracted out from the commercial tool box and fed into the PSE tool. With the help of advanced solvers, the PSE tool is able to solve each BPA hourly statemore » estimation problem within one second, which is more than 10 times faster than today’s commercial tool. This improved computational performance can help increase the reliability value of state estimation in many aspects: (1) the shorter the time required for execution of state estimation, the more time remains for operators to take appropriate actions, and/or to apply automatic or manual corrective control actions. This increases the chances of arresting or mitigating the impact of cascading failures; (2) the SE can be executed multiple times within time allowance. Therefore, the robustness of SE can be enhanced by repeating the execution of the SE with adaptive adjustments, including removing bad data and/or adjusting different initial conditions to compute a better estimate within the same time as a traditional state estimator’s single estimate. There are other benefits with the sub-second SE, such as that the PSE results can potentially be used in local and/or wide-area automatic corrective control actions that are currently dependent on raw measurements to minimize the impact of bad measurements, and provides opportunities to enhance the power grid reliability and efficiency. PSE also can enable other advanced tools that rely on SE outputs and could be used to further improve operators’ actions and automated controls to mitigate effects of severe events on the grid. The power grid continues to grow and the number of measurements is increasing at an accelerated rate due to the variety of smart grid devices being introduced. A parallel state estimation implementation will have better performance than traditional, sequential state estimation by utilizing the power of high performance computing (HPC). This increased performance positions parallel state estimators as valuable tools for operating the increasingly more complex power grid.« less

Evolutionary radiation of earless frogs in the Andes: molecular phylogenetics and habitat shifts in high-elevation terrestrial breeding frogs

PubMed Central

Lehr, Edgar; Rabosky, Daniel L.

2018-01-01

The loss of hearing structures and loss of advertisement calls in many terrestrial breeding frogs (Strabomantidae) living at high elevations in South America are common and intriguing phenomena. The Andean frog genus Phrynopus Peters, 1873 has undergone an evolutionary radiation in which most species lack the tympanic membrane and tympanic annulus, yet the phylogenetic relationships among species in this group remain largely unknown. Here, we present an expanded molecular phylogeny of Phrynopus that includes 24 nominal species. Our phylogeny includes Phrynopus peruanus, the type species of the genus, and 10 other species for which genetic data were previously unavailable. We found strong support for monophyly of Phrynopus, and that two nominal species—Phrynopus curator and Phrynopus nicoleae—are junior synonyms of Phrynopus tribulosus. Using X-ray computed tomography (CT) imaging, we demonstrate that the absence of external hearing structures is associated with complete loss of the auditory skeletal elements (columella) in at least one member of the genus. We mapped the tympanum condition on to a species tree to infer whether the loss of hearing structures took place once or multiple times. We also assessed whether tympanum condition, body size, and body shape are associated with the elevational distribution and habitat use. We identified a single evolutionary transition that involved the loss of both the tympanic membrane and tympanic annulus, which in turn is correlated with the absence of advertisement calls. We also identified several species pairs where one species inhabits the Andean grassland and the other montane forest. When accounting for phylogenetic relatedness among species, we detected a significant pattern of increasing body size with increasing elevation. Additionally, species at higher elevations tend to develop shorter limbs, shorter head, and shorter snout than species living at lower elevations. Our findings strongly suggest a link between ecological divergence and morphological diversity of terrestrial breeding frogs living in montane gradients. PMID:29492332

The effects of intermittent illumination on a visual inspection task.

PubMed

Kennedy, A; Brysbaert, M; Murray, W S

1998-02-01

Two experiments are described in which eye movements were monitored as subjects performed a simple target-spotting task under conditions of intermittent illumination produced by varying the display-screen frame rate on a computer VDU. In Experiment 1, subjects executed a saccade from a fixation point to a target which appeared randomly at a fixed eccentricity of 14 character positions to the left or right. Saccade latency did not differ reliably as a function of screen refresh rate, but average saccade extent at 70 Hz and 110 Hz was reliably shorter than at 90 Hz and 100 Hz. Experiment 2 examined the same task using a range of target eccentricities (7, 14, and 28 character positions to the left and right) and across a wider range of screen refresh rates. The results confirmed the curvilinear relationship obtained in Experiment 1, with average saccade extent reliably shorter at refresh rates of 50 Hz and 125 Hz than at 75 Hz and 100 Hz. While the effect was greater for remote targets, analyses of the proportional target error failed to show a reliable interaction between target eccentricity and display refresh rate. In contrast to Experiment 1, there was a pronounced effect of refresh rate on saccade latency (corrected for time to write the screen frame), with shorter latencies at higher refresh rates. It may be concluded that pulsation at frequencies above fusion disrupts saccade control. However, the curvilinear functional relationship between screen refresh rate and saccade extent obtained in these studies differs from previously reported effects of intermittent illumination on the average size of "entry saccades" (the first saccade to enter a given word) in a task involving word identification (Kennedy & Murray, 1993a, 1996). This conflict of data may arise in part because within-word adjustments in viewing position, which are typical of normal reading, influence measures of average saccade extent.

[Comparison of effectiveness and safety between Twisted File technique and ProTaper Universal rotary full sequence based on micro-computed tomography].

PubMed

Chen, Xiao-bo; Chen, Chen; Liang, Yu-hong

2016-02-18

To evaluate the efficacy and security of two type of rotary nickel titanium system (Twisted File and ProTaper Universal) for root canal preparation based on micro-computed tomography(micro-CT). Twenty extracted molars (including 62 canals) were divided into two experimental groups and were respectively instrumented using Twisted File rotary nickel titanium system (TF) and ProTaper Universal rotary nickel titanium system (PU) to #25/0.08 following recommended protocol. Time for root canal instrumentation (accumulation of time for every single file) was recorded. The 0-3 mm root surface from apex was observed under an optical stereomicroscope at 25 × magnification. The presence of crack line was noted. The root canals were scanned with micro-CT before and after root canal preparation. Three-dimensional shape images of canals were reconstructed, calculated and evaluated. The amount of canal central transportation of the two groups was calculated and compared. The shorter preparation time [(0.53 ± 0.14) min] was observed in TF group, while the preparation time of PU group was (2.06 ± 0.39) min (P<0.05). In mid-root level, TF group shaping resulted in less canal center transportation than PU group [(0.070 ± 0.056) mm vs. (0.097 ± 0.084) mm, P<0.05]. No instrument separation was observed in both the groups. Cracks were not found in both the groups either based in micro-CT images or observation under an optical stereomicroscope at 25 × magnification. Compared with ProTaper Universal, Twisted File took less time in root canal preparation and exhibited better shaping ability, and less canal transportation.

Jobs masonry in LHCb with elastic Grid Jobs

NASA Astrophysics Data System (ADS)

Stagni, F.; Charpentier, Ph

2015-12-01

In any distributed computing infrastructure, a job is normally forbidden to run for an indefinite amount of time. This limitation is implemented using different technologies, the most common one being the CPU time limit implemented by batch queues. It is therefore important to have a good estimate of how much CPU work a job will require: otherwise, it might be killed by the batch system, or by whatever system is controlling the jobs’ execution. In many modern interwares, the jobs are actually executed by pilot jobs, that can use the whole available time in running multiple consecutive jobs. If at some point the available time in a pilot is too short for the execution of any job, it should be released, while it could have been used efficiently by a shorter job. Within LHCbDIRAC, the LHCb extension of the DIRAC interware, we developed a simple way to fully exploit computing capabilities available to a pilot, even for resources with limited time capabilities, by adding elasticity to production MonteCarlo (MC) simulation jobs. With our approach, independently of the time available, LHCbDIRAC will always have the possibility to execute a MC job, whose length will be adapted to the available amount of time: therefore the same job, running on different computing resources with different time limits, will produce different amounts of events. The decision on the number of events to be produced is made just in time at the start of the job, when the capabilities of the resource are known. In order to know how many events a MC job will be instructed to produce, LHCbDIRAC simply requires three values: the CPU-work per event for that type of job, the power of the machine it is running on, and the time left for the job before being killed. Knowing these values, we can estimate the number of events the job will be able to simulate with the available CPU time. This paper will demonstrate that, using this simple but effective solution, LHCb manages to make a more efficient use of the available resources, and that it can easily use new types of resources. An example is represented by resources provided by batch queues, where low-priority MC jobs can be used as "masonry" jobs in multi-jobs pilots. A second example is represented by opportunistic resources with limited available time.

Simplified energy-balance model for pragmatic multi-dimensional device simulation

NASA Astrophysics Data System (ADS)

Chang, Duckhyun; Fossum, Jerry G.

1997-11-01

To pragmatically account for non-local carrier heating and hot-carrier effects such as velocity overshoot and impact ionization in multi-dimensional numerical device simulation, a new simplified energy-balance (SEB) model is developed and implemented in FLOODS[16] as a pragmatic option. In the SEB model, the energy-relaxation length is estimated from a pre-process drift-diffusion simulation using the carrier-velocity distribution predicted throughout the device domain, and is used without change in a subsequent simpler hydrodynamic (SHD) simulation. The new SEB model was verified by comparison of two-dimensional SHD and full HD DC simulations of a submicron MOSFET. The SHD simulations yield detailed distributions of carrier temperature, carrier velocity, and impact-ionization rate, which agree well with the full HD simulation results obtained with FLOODS. The most noteworthy feature of the new SEB/SHD model is its computational efficiency, which results from reduced Newton iteration counts caused by the enhanced linearity. Relative to full HD, SHD simulation times can be shorter by as much as an order of magnitude since larger voltage steps for DC sweeps and larger time steps for transient simulations can be used. The improved computational efficiency can enable pragmatic three-dimensional SHD device simulation as well, for which the SEB implementation would be straightforward as it is in FLOODS or any robust HD simulator.

Time to relapse after epilepsy surgery in children: AED withdrawal policies are a contributing factor.

PubMed

Boshuisen, Kim; Schmidt, Dieter; Uiterwaal, Cuno S P M; Arzimanoglou, Alexis; Braun, Kees P J; Study Group, TimeToStop

2014-09-01

It was recently suggested that early postoperative seizure relapse implicates a failure to define and resect the epileptogenic zone, that late recurrences reflect the persistence or re-emergence of epileptogenic pathology, and that early recurrences are associated with poor treatment response. Timing of antiepileptic drugs withdrawal policies, however, have never been taken into account when investigating time to relapse following epilepsy surgery. Of the European paediatric epilepsy surgery cohort from the "TimeToStop" study, all 95 children with postoperative seizure recurrence following antiepileptic drug (AED) withdrawal were selected. We investigated how time intervals from surgery to AED withdrawal, as well as other previously suggested determinants of (timing of) seizure recurrence, related to time to relapse and to relapse treatability. Uni- and multivariable linear and logistic regression models were used. Based on multivariable analysis, a shorter interval to AED reduction was the only independent predictor of a shorter time to relapse. Based on univariable analysis, incomplete resection of the epileptogenic zone related to a shorter time to recurrence. Timing of recurrence was not related to the chance of regaining seizure freedom after reinstallation of medical treatment. For children in whom AED reduction is initiated following epilepsy surgery, the time to relapse is largely influenced by the timing of AED withdrawal, rather than by disease or surgery-specific factors. We could not confirm a relationship between time to recurrence and treatment response. Timing of AED withdrawal should be taken into account when studying time to relapse following epilepsy surgery, as early withdrawal reveals more rapidly whether surgery had the intended curative effect, independently of the other factors involved.

TEMPORAL EVOLUTION AND SPATIAL DISTRIBUTION OF WHITE-LIGHT FLARE KERNELS IN A SOLAR FLARE

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

Kawate, T.; Ishii, T. T.; Nakatani, Y.

2016-12-10

On 2011 September 6, we observed an X2.1-class flare in continuum and H α with a frame rate of about 30 Hz. After processing images of the event by using a speckle-masking image reconstruction, we identified white-light (WL) flare ribbons on opposite sides of the magnetic neutral line. We derive the light curve decay times of the WL flare kernels at each resolution element by assuming that the kernels consist of one or two components that decay exponentially, starting from the peak time. As a result, 42% of the pixels have two decay-time components with average decay times of 15.6 andmore » 587 s, whereas the average decay time is 254 s for WL kernels with only one decay-time component. The peak intensities of the shorter decay-time component exhibit good spatial correlation with the WL intensity, whereas the peak intensities of the long decay-time components tend to be larger in the early phase of the flare at the inner part of the flare ribbons, close to the magnetic neutral line. The average intensity of the longer decay-time components is 1.78 times higher than that of the shorter decay-time components. If the shorter decay time is determined by either the chromospheric cooling time or the nonthermal ionization timescale and the longer decay time is attributed to the coronal cooling time, this result suggests that WL sources from both regions appear in 42% of the WL kernels and that WL emission of the coronal origin is sometimes stronger than that of chromospheric origin.« less

Minimally invasive and computer-navigated total hip arthroplasty: a qualitative and systematic review of the literature

PubMed Central

2010-01-01

Background Both minimally invasive surgery (MIS) and computer-assisted surgery (CAS) for total hip arthroplasty (THA) have gained popularity in recent years. We conducted a qualitative and systematic review to assess the effectiveness of MIS, CAS and computer-assisted MIS for THA. Methods An extensive computerised literature search of PubMed, Medline, Embase and OVIDSP was conducted. Both randomised clinical trials and controlled clinical trials on the effectiveness of MIS, CAS and computer-assisted MIS for THA were included. Methodological quality was independently assessed by two reviewers. Effect estimates were calculated and a best-evidence synthesis was performed. Results Four high-quality and 14 medium-quality studies with MIS THA as study contrast, and three high-quality and four medium-quality studies with CAS THA as study contrast were included. No studies with computer-assisted MIS for THA as study contrast were identified. Strong evidence was found for a decrease in operative time and intraoperative blood loss for MIS THA, with no difference in complication rates and risk for acetabular outliers. Strong evidence exists that there is no difference in physical functioning, measured either by questionnaires or by gait analysis. Moderate evidence was found for a shorter length of hospital stay after MIS THA. Conflicting evidence was found for a positive effect of MIS THA on pain in the early postoperative period, but that effect diminished after three months postoperatively. Strong evidence was found for an increase in operative time for CAS THA, and limited evidence was found for a decrease in intraoperative blood loss. Furthermore, strong evidence was found for no difference in complication rates, as well as for a significantly lower risk for acetabular outliers. Conclusions The results indicate that MIS THA is a safe surgical procedure, without increases in operative time, blood loss, operative complication rates and component malposition rates. However, the beneficial effect of MIS THA on functional recovery has to be proven. The results also indicate that CAS THA, though resulting in an increase in operative time, may have a positive effect on operative blood loss and operative complication rates. More importantly, the use of CAS results in better positioning of acetabular component of the prosthesis. PMID:20470443

Human short-term exposure to electromagnetic fields emitted by mobile phones decreases computer-assisted visual reaction time.

PubMed

Mortazavi, S M J; Rouintan, M S; Taeb, S; Dehghan, N; Ghaffarpanah, A A; Sadeghi, Z; Ghafouri, F

2012-06-01

The worldwide dramatic increase in mobile phone use has generated great concerns about the detrimental effects of microwave radiations emitted by these communication devices. Reaction time plays a critical role in performing tasks necessary to avoid hazards. As far as we know, this study is the first survey that reports decreased reaction time after exposure to electromagnetic fields generated by a high specific absorption rate mobile phone. It is also the first study in which previous history of mobile phone use is taken into account. The aim of this study was to assess both the acute and chronic effects of electromagnetic fields emitted by mobile phones on reaction time in university students. Visual reaction time (VRT) of young university students was recorded with a simple blind computer-assisted-VRT test, before and after a 10 min real/sham exposure to electromagnetic fields of mobile phones. Participants were 160 right-handed university students aged 18-31. To assess the effect of chronic exposures, the reaction time in sham-exposed phases were compared among low level, moderate and frequent users of mobile phones. The mean ± SD reaction time after real exposure and sham exposure were 286.78 ± 31.35 ms and 295.86 ± 32.17 ms (P < 0.001), respectively. The age of students did not significantly alter the reaction time either in talk or in standby mode. The reaction time either in talk or in standby mode was shorter in male students. The students' VRT was significantly affected by exposure to electromagnetic fields emitted by a mobile phone. It can be concluded that these exposures cause decreased reaction time, which may lead to a better response to different hazards. In this light, this phenomenon might decrease the chances of human errors and fatal accidents.

Modeling of ablation threshold dependence on pulse duration for dielectrics with ultrashort pulsed laser

NASA Astrophysics Data System (ADS)

Sun, Mingying; Zhu, Jianqiang; Lin, Zunqi

2017-01-01

We present a numerical model of plasma formation in ultrafast laser ablation on the dielectrics surface. Ablation threshold dependence on pulse duration is predicted with the model and the numerical results for water agrees well with the experimental data for pulse duration from 140 fs to 10 ps. Influences of parameters and approximations of photo- and avalanche-ionization on the ablation threshold prediction are analyzed in detail for various pulse lengths. The calculated ablation threshold is strongly dependent on electron collision time for all the pulse durations. The complete photoionization model is preferred for pulses shorter than 1 ps rather than the multiphoton ionization approximations. The transition time of inverse bremsstrahlung absorption needs to be considered when pulses are shorter than 5 ps and it can also ensure the avalanche ionization (AI) coefficient consistent with that in multiple rate equations (MREs) for pulses shorter than 300 fs. The threshold electron density for AI is only crucial for longer pulses. It is reasonable to ignore the recombination loss for pulses shorter than 100 fs. In addition to thermal transport and hydrodynamics, neglecting the threshold density for AI and recombination could also contribute to the disagreements between the numerical and the experimental results for longer pulses.

Denosumab and Bone Metastasis–Free Survival in Men With Nonmetastatic Castration-Resistant Prostate Cancer: Exploratory Analyses by Baseline Prostate-Specific Antigen Doubling Time

PubMed Central

Smith, Matthew R.; Saad, Fred; Oudard, Stephane; Shore, Neal; Fizazi, Karim; Sieber, Paul; Tombal, Bertrand; Damiao, Ronaldo; Marx, Gavin; Miller, Kurt; Van Veldhuizen, Peter; Morote, Juan; Ye, Zhishen; Dansey, Roger; Goessl, Carsten

2013-01-01

Purpose Denosumab, an anti–RANK ligand monoclonal antibody, significantly increases bone metastasis–free survival (BMFS; hazard ratio [HR], 0.85; P = .028) and delays time to first bone metastasis in men with nonmetastatic castration-resistant prostate cancer (CRPC) and baseline prostate-specific antigen (PSA) ≥ 8.0 ng/mL and/or PSA doubling time (PSADT) ≤ 10.0 months. To identify men at greatest risk for bone metastasis or death, we evaluated relationships between PSA and PSADT with BMFS in the placebo group and the efficacy and safety of denosumab in men with PSADT ≤ 10, ≤ 6, and ≤ 4 months. Patients and Methods A total of 1,432 men with nonmetastatic CRPC were randomly assigned 1:1 to monthly subcutaneous denosumab 120 mg or placebo. Enrollment began February 2006; primary analysis cutoff was July 2010, when approximately 660 men were anticipated to have developed bone metastases or died. Results In the placebo group, shorter BMFS was observed as PSADT decreased below 8 months. In analyses by shorter baseline PSADT, denosumab consistently increased BMFS by a median of 6.0, 7.2, and 7.5 months among men with PSADT ≤ 10 (HR, 0.84; P = .042), ≤ 6 (HR, 0.77; P = .006), and ≤ 4 months (HR, 0.71; P = .004), respectively. Denosumab also consistently increased time to bone metastasis by PSADT subset. No difference in survival was observed between treatment groups for the overall study population or PSADT subsets. Conclusion Patients with shorter PSADT are at greater risk for bone metastasis or death. Denosumab consistently improves BMFS in men with shorter PSADT and seems to have the greatest treatment effects in men at high risk for progression. PMID:24043751

Denosumab and bone metastasis-free survival in men with nonmetastatic castration-resistant prostate cancer: exploratory analyses by baseline prostate-specific antigen doubling time.

PubMed

Smith, Matthew R; Saad, Fred; Oudard, Stephane; Shore, Neal; Fizazi, Karim; Sieber, Paul; Tombal, Bertrand; Damiao, Ronaldo; Marx, Gavin; Miller, Kurt; Van Veldhuizen, Peter; Morote, Juan; Ye, Zhishen; Dansey, Roger; Goessl, Carsten

2013-10-20

Denosumab, an anti-RANK ligand monoclonal antibody, significantly increases bone metastasis-free survival (BMFS; hazard ratio [HR], 0.85; P = .028) and delays time to first bone metastasis in men with nonmetastatic castration-resistant prostate cancer (CRPC) and baseline prostate-specific antigen (PSA) ≥ 8.0 ng/mL and/or PSA doubling time (PSADT) ≤ 10.0 months. To identify men at greatest risk for bone metastasis or death, we evaluated relationships between PSA and PSADT with BMFS in the placebo group and the efficacy and safety of denosumab in men with PSADT ≤ 10, ≤ 6, and ≤ 4 months. A total of 1,432 men with nonmetastatic CRPC were randomly assigned 1:1 to monthly subcutaneous denosumab 120 mg or placebo. Enrollment began February 2006; primary analysis cutoff was July 2010, when approximately 660 men were anticipated to have developed bone metastases or died. In the placebo group, shorter BMFS was observed as PSADT decreased below 8 months. In analyses by shorter baseline PSADT, denosumab consistently increased BMFS by a median of 6.0, 7.2, and 7.5 months among men with PSADT ≤ 10 (HR, 0.84; P = .042), ≤ 6 (HR, 0.77; P = .006), and ≤ 4 months (HR, 0.71; P = .004), respectively. Denosumab also consistently increased time to bone metastasis by PSADT subset. No difference in survival was observed between treatment groups for the overall study population or PSADT subsets. Patients with shorter PSADT are at greater risk for bone metastasis or death. Denosumab consistently improves BMFS in men with shorter PSADT and seems to have the greatest treatment effects in men at high risk for progression.

Clinical and molecular predictors of disease severity and survival in chronic lymphocytic leukemia.

PubMed

Weinberg, J Brice; Volkheimer, Alicia D; Chen, Youwei; Beasley, Bethany E; Jiang, Ning; Lanasa, Mark C; Friedman, Daphne; Vaccaro, Gina; Rehder, Catherine W; Decastro, Carlos M; Rizzieri, David A; Diehl, Louis F; Gockerman, Jon P; Moore, Joseph O; Goodman, Barbara K; Levesque, Marc C

2007-12-01

Several parameters may predict disease severity and overall survival in chronic lymphocytic leukemia (CLL). The purpose of our study of 190 CLL patients was to compare immunoglobulin heavy chain variable region (IgV(H)) mutation status, cytogenetic abnormalities, and leukemia cell CD38 and Zap-70 to older, traditional parameters. We also wanted to construct a simple, inexpensive prognosis score that would significantly predict TTT and survival in patients at the time of diagnosis and help practicing clinicians. In univariate analyses, patients with higher clinical stage, higher leukocyte count at diagnosis, shorter leukocyte doubling time, elevated serum lactate dehydrogenase (LDH), unmutated immunoglobulin heavy chain variable region (IgV(H)) genes, and higher CD38 had a shorter overall survival and time-to-treatment (TTT). CLL cell Zap-70 expression was higher in patients with unmutated IgV(H), and those with higher Zap-70 tended to have shorter survival. IgV(H)4-34 or IgV(H)1-69 was the most common IgV(H) genes used (16 and 12%, respectively). Of those with IgV(H)1-69, 86% had unmutated IgV(H) and had a significantly shorter TTT. A cytogenetic abnormality was noted in 71% of the patients tested. Patients with 11q22 del and 17p13 del or complex abnormalities were significantly more likely to have unmutated IgV(H). We found that a prognostic score constructed using modified Rai stage, cellular CD38, and serum LDH (parameters easily obtained clinically) significantly predicted TTT and survival in patients at the time of diagnosis and performed as well or better than models using the newer markers.

The Role of Prophylactic Endoscopic Sphincterotomy for Prevention of Postoperative Bile Leak in Hydatid Liver Disease: A Randomized Controlled Study.

PubMed

El-Gendi, Ahmed M; El-Shafei, Mohamed; Bedewy, Essam

2018-03-12

Bile leak is the main cause of morbidity and mortality after surgery for hydatid liver cysts. Aim was to assess the role of prophylactic endoscopic sphincterotomy (ES) in reducing postoperative bile leak in patients undergoing partial cystectomy. Fifty-four patients with hepatic hydatid cyst met inclusion criteria, 27 were excluded or declined to participate. Twenty-six women and 28 men (mean age 44.6 ± 10.1, range: 22-61 years) were randomly assigned to either group I with ES (n = 27) or group II without ES (n = 27). Demographics and clinical, laboratory, and radiological characteristics of cysts were not statistically different between two groups. Group I had a significant decrease in bile leak rate compared with group II (11.1% versus 40.7%, P = .013), with significantly shorter duration of hospital stay (P < .0001). Biliary fistula in group I had significantly lower daily output (100 mL/day versus 350 mL/day) with gradual reduction till stoppage of leak in 3-4 days without intervention. Biliary fistula in group II had a significantly higher need for biliary intervention through postoperative endoscopic retrograde cholangiopancreatography with ES compared with biliary fistula in group I ( FE P = .002), with significantly longer mean time of fistula closure (P = .011) and longer time to drain removal (P < .0001). Nonbiliary complications were comparable between two groups. Prophylactic ES provides significant reduction in postoperative bile leak rate with shorter hospital stay after partial cystectomy of hydatid cyst. Biliary fistula in patients with ES has significantly lower daily output with shorter time of drain removal and shorter time to closure than patients without ES.

Advanced optical network architecture for integrated digital avionics

NASA Astrophysics Data System (ADS)

Morgan, D. Reed

1996-12-01

For the first time in the history of avionics, the network designer now has a choice in selecting the media that interconnects the sources and sinks of digital data on aircraft. Electrical designs are already giving way to photonics in application areas where the data rate times distance product is large or where special design requirements such as low weight or EMI considerations are critical. Future digital avionic architectures will increasingly favor the use of photonic interconnects as network data rates of one gigabit/second and higher are needed to support real-time operation of high-speed integrated digital processing. As the cost of optical network building blocks is reduced and as temperature-rugged laser sources are matured, metal interconnects will be forced to retreat to applications spanning shorter and shorter distances. Although the trend is already underway, the widespread use of digital optics will first occur at the system level, where gigabit/second, real-time interconnects between sensors, processors, mass memories and displays separated by a least of few meters will be required. The application of photonic interconnects for inter-printed wiring board signalling across the backplane will eventually find application for gigabit/second applications since signal degradation over copper traces occurs before one gigabit/second and 0.5 meters are reached. For the foreseeable future however, metal interconnects will continue to be used to interconnect devices on printed wiring boards since 5 gigabit/second signals can be sent over metal up to around 15 centimeters. Current-day applications of optical interconnects at the system level are described and a projection of how advanced optical interconnect technology will be driven by the use of high speed integrated digital processing on future aircraft is presented. The recommended advanced network for application in the 2010 time frame is a fiber-based system with a signalling speed of around 2-3 gigabits per second. This switch-based unified network will interconnect sensors, displays, mass memory and controls and displays to computer modules within the processing complex. The characteristics of required building blocks needed for the future are described. These building blocks include the fiber, an optical switch, a laser-based transceiver, blind-mate connectors and an optical backplane.

An application of a relational database system for high-throughput prediction of elemental compositions from accurate mass values.

PubMed

Sakurai, Nozomu; Ara, Takeshi; Kanaya, Shigehiko; Nakamura, Yukiko; Iijima, Yoko; Enomoto, Mitsuo; Motegi, Takeshi; Aoki, Koh; Suzuki, Hideyuki; Shibata, Daisuke

2013-01-15

High-accuracy mass values detected by high-resolution mass spectrometry analysis enable prediction of elemental compositions, and thus are used for metabolite annotations in metabolomic studies. Here, we report an application of a relational database to significantly improve the rate of elemental composition predictions. By searching a database of pre-calculated elemental compositions with fixed kinds and numbers of atoms, the approach eliminates redundant evaluations of the same formula that occur in repeated calculations with other tools. When our approach is compared with HR2, which is one of the fastest tools available, our database search times were at least 109 times shorter than those of HR2. When a solid-state drive (SSD) was applied, the search time was 488 times shorter at 5 ppm mass tolerance and 1833 times at 0.1 ppm. Even if the search by HR2 was performed with 8 threads in a high-spec Windows 7 PC, the database search times were at least 26 and 115 times shorter without and with the SSD. These improvements were enhanced in a low spec Windows XP PC. We constructed a web service 'MFSearcher' to query the database in a RESTful manner. Available for free at http://webs2.kazusa.or.jp/mfsearcher. The web service is implemented in Java, MySQL, Apache and Tomcat, with all major browsers supported. sakurai@kazusa.or.jp Supplementary data are available at Bioinformatics online.

Quantitative contrast-enhanced ultrasonography for the differential diagnosis of endometrial hyperplasia and endometrial neoplasms

PubMed Central

Liu, Ying; Xu, Yi; Cheng, Wen; Liu, Xinghan

2016-01-01

The present study aimed to investigate the feasibility of applying contrast-enhanced ultrasonography (CEUS) imaging technology for distinguishing between benign and malignant endometrial lesions, and to screen markers that could be correlated with the pathological results. In this study, endometrial diseases were diagnosed by biopsy under hysteroscopy and CEUS examinations. The intensity and time parameters of the time-intensity curve (TIC) were analyzed. The mean arrival time (AT), time-to-peak (TTP), rise time (RT), washout half-time and clearance half-time of malignant lesions were shorter than those of benign lesions (P<0.05), whereas the average peak intensity (PI) and enhancement intensity (EI) of malignant lesions were higher than those of benign lesions (P<0.05). The receiver operating characteristic curve showed the following cut-off values: PI, 29.2 dB; EI, 21.35 dB; AT, 12.75 sec; TTP, 26.75 sec; RT, 13.2 sec; clearance half-time, 89.3 sec; and washout half-time, 75.45 sec. The lesions with PI, an EI higher than that of the cut-off and lesions with an AT, TTP, RT, half clearing time and washout half-time shorter than the cut-off were considered malignant. The TTP, RT and half clearing time were negatively correlated with microvessel density (MVD), i.e., MVD was higher when the TTP, RT and half clearing time were shorter. Overall, changes in the enhancement and clearing of lesions could be quantitatively analyzed by CEUS TIC and further discriminate benign from malignant lesions. In the present study, CEUS appeared to indirectly reflect blood vessel changes inside the lesions and provided a pre-operative non-invasive fast imaging method for the diagnosis of endometrial disease. PMID:27895728

An interactive program to display user-generated or file-based maps on a personal computer monitor

USGS Publications Warehouse

Langer, W.H.; Stephens, R.W.

1987-01-01

PC MAP-MAKER is an ADVANCED BASIC program written to provide users of IBM XT, IBM AT, and compatible computers with a straight-forward, flexible method to display geographical data on a color or monochrome PC (personal computer) monitor. Data can be political boundaries such as State and county boundaries; natural curvilinear features such as rivers, drainage areas, and geological contacts; and points such as well locations and mineral localities. Essentially any point defined by a latitude and longitude and any line defined by a series of latitude and longitude values can be displayed using the program. PC MAP MAKER allows users to view tabular data from U.S. Geological Survey files such as WATSTORE (National Water Data Storage and Retrieval System) in a map format in a time much shorter than required by sending the data to a line plotter. The screen image can be saved to disk for recall at a later date, and hard copies can be printed with a dot matrix printer. The program is user-friendly, using menus or prompts to guide user input. It is fully documented and structured to allow the user to tailor the program to the user 's specific needs. The documentation includes a tutorial designed to introduce users to the capabilities of the program using the State of Colorado as a demonstration map area. (Author 's abstract)

Relativistic force field: parametric computations of proton-proton coupling constants in (1)H NMR spectra.

PubMed

Kutateladze, Andrei G; Mukhina, Olga A

2014-09-05

Spin-spin coupling constants in (1)H NMR carry a wealth of structural information and offer a powerful tool for deciphering molecular structures. However, accurate ab initio or DFT calculations of spin-spin coupling constants have been very challenging and expensive. Scaling of (easy) Fermi contacts, fc, especially in the context of recent findings by Bally and Rablen (Bally, T.; Rablen, P. R. J. Org. Chem. 2011, 76, 4818), offers a framework for achieving practical evaluation of spin-spin coupling constants. We report a faster and more precise parametrization approach utilizing a new basis set for hydrogen atoms optimized in conjunction with (i) inexpensive B3LYP/6-31G(d) molecular geometries, (ii) inexpensive 4-31G basis set for carbon atoms in fc calculations, and (iii) individual parametrization for different atom types/hybridizations, not unlike a force field in molecular mechanics, but designed for the fc's. With the training set of 608 experimental constants we achieved rmsd <0.19 Hz. The methodology performs very well as we illustrate with a set of complex organic natural products, including strychnine (rmsd 0.19 Hz), morphine (rmsd 0.24 Hz), etc. This precision is achieved with much shorter computational times: accurate spin-spin coupling constants for the two conformers of strychnine were computed in parallel on two 16-core nodes of a Linux cluster within 10 min.

High throughput and quantitative approaches for measuring circadian rhythms in cyanobacteria using bioluminescence

PubMed Central

Shultzaberger, Ryan K.; Paddock, Mark L.; Katsuki, Takeo; Greenspan, Ralph J.; Golden, Susan S.

2016-01-01

The temporal measurement of a bioluminescent reporter has proven to be one of the most powerful tools for characterizing circadian rhythms in the cyanobacterium Synechococcus elongatus. Primarily, two approaches have been used to automate this process: (1) detection of cell culture bioluminescence in 96-well plates by a photomultiplier tube-based plate-cycling luminometer (TopCount Microplate Scintillation and Luminescence Counter, Perkin Elmer) and (2) detection of individual colony bioluminescence by iteratively rotating a Petri dish under a cooled CCD camera using a computer-controlled turntable. Each approach has distinct advantages. The TopCount provides a more quantitative measurement of bioluminescence, enabling the direct comparison of clock output levels among strains. The computer-controlled turntable approach has a shorter set-up time and greater throughput, making it a more powerful phenotypic screening tool. While the latter approach is extremely useful, only a few labs have been able to build such an apparatus because of technical hurdles involved in coordinating and controlling both the camera and the turntable, and in processing the resulting images. This protocol provides instructions on how to construct, use, and process data from a computer-controlled turntable to measure the temporal changes in bioluminescence of individual cyanobacterial colonies. Furthermore, we describe how to prepare samples for use with the TopCount to minimize experimental noise, and generate meaningful quantitative measurements of clock output levels for advanced analysis. PMID:25662451

Simulation Environment Synchronizing Real Equipment for Manufacturing Cell

NASA Astrophysics Data System (ADS)

Inukai, Toshihiro; Hibino, Hironori; Fukuda, Yoshiro

Recently, manufacturing industries face various problems such as shorter product life cycle, more diversified customer needs. In this situation, it is very important to reduce lead-time of manufacturing system constructions. At the manufacturing system implementation stage, it is important to make and evaluate facility control programs for a manufacturing cell, such as ladder programs for programmable logical controllers (PLCs) rapidly. However, before the manufacturing systems are implemented, methods to evaluate the facility control programs for the equipment while mixing and synchronizing real equipment and virtual factory models on the computers have not been developed. This difficulty is caused by the complexity of the manufacturing system composed of a great variety of equipment, and stopped precise and rapid support of a manufacturing engineering process. In this paper, a manufacturing engineering environment (MEE) to support manufacturing engineering processes using simulation technologies is proposed. MEE consists of a manufacturing cell simulation environment (MCSE) and a distributed simulation environment (DSE). MCSE, which consists of a manufacturing cell simulator and a soft-wiring system, is emphatically proposed in detail. MCSE realizes making and evaluating facility control programs by using virtual factory models on computers before manufacturing systems are implemented.

High-frequency signal and noise estimates of CSR GRACE RL04

NASA Astrophysics Data System (ADS)

Bonin, Jennifer A.; Bettadpur, Srinivas; Tapley, Byron D.

2012-12-01

A sliding window technique is used to create daily-sampled Gravity Recovery and Climate Experiment (GRACE) solutions with the same background processing as the official CSR RL04 monthly series. By estimating over shorter time spans, more frequent solutions are made using uncorrelated data, allowing for higher frequency resolution in addition to daily sampling. Using these data sets, high-frequency GRACE errors are computed using two different techniques: assuming the GRACE high-frequency signal in a quiet area of the ocean is the true error, and computing the variance of differences between multiple high-frequency GRACE series from different centers. While the signal-to-noise ratios prove to be sufficiently high for confidence at annual and lower frequencies, at frequencies above 3 cycles/year the signal-to-noise ratios in the large hydrological basins looked at here are near 1.0. Comparisons with the GLDAS hydrological model and high frequency GRACE series developed at other centers confirm CSR GRACE RL04's poor ability to accurately and reliably measure hydrological signal above 3-9 cycles/year, due to the low power of the large-scale hydrological signal typical at those frequencies compared to the GRACE errors.

The Use of Object-Oriented Analysis Methods in Surety Analysis

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

Craft, Richard L.; Funkhouser, Donald R.; Wyss, Gregory D.

1999-05-01

Object-oriented analysis methods have been used in the computer science arena for a number of years to model the behavior of computer-based systems. This report documents how such methods can be applied to surety analysis. By embodying the causality and behavior of a system in a common object-oriented analysis model, surety analysts can make the assumptions that underlie their models explicit and thus better communicate with system designers. Furthermore, given minor extensions to traditional object-oriented analysis methods, it is possible to automatically derive a wide variety of traditional risk and reliability analysis methods from a single common object model. Automaticmore » model extraction helps ensure consistency among analyses and enables the surety analyst to examine a system from a wider variety of viewpoints in a shorter period of time. Thus it provides a deeper understanding of a system's behaviors and surety requirements. This report documents the underlying philosophy behind the common object model representation, the methods by which such common object models can be constructed, and the rules required to interrogate the common object model for derivation of traditional risk and reliability analysis models. The methodology is demonstrated in an extensive example problem.« less

Performance evaluation of an improved optical computed tomography polymer gel dosimeter system for 3D dose verification of static and dynamic phantom deliveries

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

Lopatiuk-Tirpak, O.; Langen, K. M.; Meeks, S. L.

2008-09-15

The performance of a next-generation optical computed tomography scanner (OCTOPUS-5X) is characterized in the context of three-dimensional gel dosimetry. Large-volume (2.2 L), muscle-equivalent, radiation-sensitive polymer gel dosimeters (BANG-3) were used. Improvements in scanner design leading to shorter acquisition times are discussed. The spatial resolution, detectable absorbance range, and reproducibility are assessed. An efficient method for calibrating gel dosimeters using the depth-dose relationship is applied, with photon- and electron-based deliveries yielding equivalent results. A procedure involving a preirradiation scan was used to reduce the edge artifacts in reconstructed images, thereby increasing the useful cross-sectional area of the dosimeter by nearly amore » factor of 2. Dose distributions derived from optical density measurements using the calibration coefficient show good agreement with the treatment planning system simulations and radiographic film measurements. The feasibility of use for motion (four-dimensional) dosimetry is demonstrated on an example comparing dose distributions from static and dynamic delivery of a single-field photon plan. The capability to visualize three-dimensional dose distributions is also illustrated.« less

Multilocus lod scores in large pedigrees: combination of exact and approximate calculations.

PubMed

Tong, Liping; Thompson, Elizabeth

2008-01-01

To detect the positions of disease loci, lod scores are calculated at multiple chromosomal positions given trait and marker data on members of pedigrees. Exact lod score calculations are often impossible when the size of the pedigree and the number of markers are both large. In this case, a Markov Chain Monte Carlo (MCMC) approach provides an approximation. However, to provide accurate results, mixing performance is always a key issue in these MCMC methods. In this paper, we propose two methods to improve MCMC sampling and hence obtain more accurate lod score estimates in shorter computation time. The first improvement generalizes the block-Gibbs meiosis (M) sampler to multiple meiosis (MM) sampler in which multiple meioses are updated jointly, across all loci. The second one divides the computations on a large pedigree into several parts by conditioning on the haplotypes of some 'key' individuals. We perform exact calculations for the descendant parts where more data are often available, and combine this information with sampling of the hidden variables in the ancestral parts. Our approaches are expected to be most useful for data on a large pedigree with a lot of missing data. (c) 2007 S. Karger AG, Basel

Multilocus Lod Scores in Large Pedigrees: Combination of Exact and Approximate Calculations

PubMed Central

Tong, Liping; Thompson, Elizabeth

2007-01-01

To detect the positions of disease loci, lod scores are calculated at multiple chromosomal positions given trait and marker data on members of pedigrees. Exact lod score calculations are often impossible when the size of the pedigree and the number of markers are both large. In this case, a Markov Chain Monte Carlo (MCMC) approach provides an approximation. However, to provide accurate results, mixing performance is always a key issue in these MCMC methods. In this paper, we propose two methods to improve MCMC sampling and hence obtain more accurate lod score estimates in shorter computation time. The first improvement generalizes the block-Gibbs meiosis (M) sampler to multiple meiosis (MM) sampler in which multiple meioses are updated jointly, across all loci. The second one divides the computations on a large pedigree into several parts by conditioning on the haplotypes of some ‘key’ individuals. We perform exact calculations for the descendant parts where more data are often available, and combine this information with sampling of the hidden variables in the ancestral parts. Our approaches are expected to be most useful for data on a large pedigree with a lot of missing data. PMID:17934317

Comparison of stresses on homogeneous spheroids in the optical stretcher computed with geometrical optics and generalized Lorenz-Mie theory.

PubMed

Boyde, Lars; Ekpenyong, Andrew; Whyte, Graeme; Guck, Jochen

2012-11-20

We present two electromagnetic frameworks to compare the surface stresses on spheroidal particles in the optical stretcher (a dual-beam laser trap that can be used to capture and deform biological cells). The first model is based on geometrical optics (GO) and limited in its applicability to particles that are much greater than the incident wavelength. The second framework is more sophisticated and hinges on the generalized Lorenz-Mie theory (GLMT). Despite the difference in complexity between both theories, the stress profiles computed with GO and GLMT are in good agreement with each other (relative errors are on the order of 1-10%). Both models predict a diminishing of the stresses for larger wavelengths and a strong increase of the stresses for shorter laser-cell distances. Results indicate that surface stresses on a spheroid with an aspect ratio of 1.2 hardly differ from the stresses on a sphere of similar size. Knowledge of the surface stresses and whether or not they redistribute during the stretching process is of crucial importance in real-time applications of the stretcher that aim to discern the viscoelastic properties of cells for purposes of cell characterization, sorting, and medical diagnostics.

Progress towards daily "swath" solutions from GRACE

NASA Astrophysics Data System (ADS)

Save, H.; Bettadpur, S. V.; Sakumura, C.

2015-12-01

The GRACE mission has provided invaluable and the only data of its kind that measures the total water column in the Earth System over the past 13 years. The GRACE solutions available from the project have been monthly average solutions. There have been attempts by several groups to produce shorter time-window solutions with different techniques. There is also an experimental quick-look GRACE solution available from CSR that implements a sliding window approach while applying variable daily data weights. All of these GRACE solutions require special handling for data assimilation. This study explores the possibility of generating a true daily GRACE solution by computing a daily "swath" total water storage (TWS) estimate from GRACE using the Tikhonov regularization and high resolution monthly mascon estimation implemented at CSR. This paper discusses the techniques for computing such a solution and discusses the error and uncertainty characterization. We perform comparisons with official RL05 GRACE solutions and with alternate mascon solutions from CSR to understand the impact on the science results. We evaluate these solutions with emphasis on the temporal characteristics of the signal content and validate them against multiple models and in-situ data sets.

Optimal reactive planning with security constraints

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

Thomas, W.R.; Cheng, D.T.Y.; Dixon, A.M.

1995-12-31

The National Grid Company (NGC) of England and Wales has developed a computer program, SCORPION, to help system planners optimize the location and size of new reactive compensation plant on the transmission system. The reactive power requirements of the NGC system have risen as a result of increased power flows and the shorter timescale on which power stations are commissioned and withdrawn from service. In view of the high costs involved, it is important that reactive compensation be installed as economically as possible, without compromising security. Traditional methods based on iterative use of a load flow program are labor intensivemore » and subjective. SCORPION determines a near-optimal pattern of new reactive sources which are required to satisfy voltage constraints for normal and contingent states of operation of the transmission system. The algorithm processes the system states sequentially, instead of optimizing all of them simultaneously. This allows a large number of system states to be considered with an acceptable run time and computer memory requirement. Installed reactive sources are treated as continuous, rather than discrete, variables. However, the program has a restart facility which enables the user to add realistically sized reactive sources explicitly and thereby work towards a realizable solution to the planning problem.« less

Computer use, sleep duration and health symptoms: a cross-sectional study of 15-year olds in three countries.

PubMed

Nuutinen, Teija; Roos, Eva; Ray, Carola; Villberg, Jari; Välimaa, Raili; Rasmussen, Mette; Holstein, Bjørn; Godeau, Emmanuelle; Beck, Francois; Léger, Damien; Tynjälä, Jorma

2014-08-01

This study investigated whether computer use is associated with health symptoms through sleep duration among 15-year olds in Finland, France and Denmark. We used data from the WHO cross-national Health Behaviour in School-aged Children study collected in Finland, France and Denmark in 2010, including data on 5,402 adolescents (mean age 15.61 (SD 0.37), girls 53%). Symptoms assessed included feeling low, irritability/bad temper, nervousness, headache, stomachache, backache, and feeling dizzy. We used structural equation modeling to explore the mediating effect of sleep duration on the association between computer use and symptom load. Adolescents slept approximately 8 h a night and computer use was approximately 2 h a day. Computer use was associated with shorter sleep duration and higher symptom load. Sleep duration partly mediated the association between computer use and symptom load, but the indirect effects of sleep duration were quite modest in all countries. Sleep duration may be a potential underlying mechanism behind the association between computer use and health symptoms.

Trends in computer hardware and software.

PubMed

Frankenfeld, F M

1993-04-01

Previously identified and current trends in the development of computer systems and in the use of computers for health care applications are reviewed. Trends identified in a 1982 article were increasing miniaturization and archival ability, increasing software costs, increasing software independence, user empowerment through new software technologies, shorter computer-system life cycles, and more rapid development and support of pharmaceutical services. Most of these trends continue today. Current trends in hardware and software include the increasing use of reduced instruction-set computing, migration to the UNIX operating system, the development of large software libraries, microprocessor-based smart terminals that allow remote validation of data, speech synthesis and recognition, application generators, fourth-generation languages, computer-aided software engineering, object-oriented technologies, and artificial intelligence. Current trends specific to pharmacy and hospitals are the withdrawal of vendors of hospital information systems from the pharmacy market, improved linkage of information systems within hospitals, and increased regulation by government. The computer industry and its products continue to undergo dynamic change. Software development continues to lag behind hardware, and its high cost is offsetting the savings provided by hardware.

Race walking gait and its influence on race walking economy in world-class race walkers.

PubMed

Gomez-Ezeiza, Josu; Torres-Unda, Jon; Tam, Nicholas; Irazusta, Jon; Granados, Cristina; Santos-Concejero, Jordan

2018-03-06

The aim of this study was to determine the relationships between biomechanical parameters of the gait cycle and race walking economy in world-class Olympic race walkers. Twenty-One world-class race walkers possessing the Olympic qualifying standard participated in this study. Participants completed an incremental race walking test starting at 10 km·h -1 , where race walking economy (ml·kg -1 ·km -1 ) and spatiotemporal gait variables were analysed at different speeds. 20-km race walking performance was related to race walking economy, being the fastest race walkers those displaying reduced oxygen cost at a given speed (R = 0.760, p < 0.001). Longer ground contact times, shorter flight times, longer midstance sub-phase and shorter propulsive sub-phase during stance were related to a better race walking economy (moderate effect, p < 0.05). According to the results of this study, the fastest race walkers were more economi cal than the lesser performers. Similarly, shorter flight times are associated with a more efficient race walking economy. Coaches and race walkers should avoid modifying their race walking style by increasing flight times, as it may not only impair economy, but also lead to disqualification.

The Development of Psychiatric Services Providing an Alternative to Full-Time Hospitalization Is Associated with Shorter Length of Stay in French Public Psychiatry.

PubMed

Gandré, Coralie; Gervaix, Jeanne; Thillard, Julien; Macé, Jean-Marc; Roelandt, Jean-Luc; Chevreul, Karine

2017-03-21

International recommendations for mental health care have advocated for a reduction in the length of stay (LOS) in full-time hospitalization and the development of alternatives to full-time hospitalizations (AFTH) could facilitate alignment with those recommendations. Our objective was therefore to assess whether the development of AFTH in French psychiatric sectors was associated with a reduction in the LOS in full-time hospitalization. Using data from the French national discharge database of psychiatric care, we computed the LOS of patients admitted for full-time hospitalization. The level of development of AFTH was estimated by the share of human resources allocated to those alternatives in the hospital enrolling the staff of each sector. Multi-level modelling was carried out to adjust the analysis on other factors potentially associated with the LOS (patients', psychiatric sectors' and environmental characteristics). We observed considerable variations in the LOS between sectors. Although the majority of these variations resulted from patients' characteristics, a significant negative association was found between the LOS and the development of AFTH, after adjusting for other factors. Our results provide first evidence of the impact of the development of AFTH on mental health care and will provide a lever for policy makers to further develop these alternatives.

Evaluation of technology to identify and assess overweight children and adolescents.

PubMed

Gance-Cleveland, Bonnie; Gilbert, Lynn H; Kopanos, Taynin; Gilbert, Kevin C

2010-01-01

The current obesity epidemic has produced a generation of children that may be the first to have a life expectancy shorter than their parents. To address the obesity epidemic, experts have published recommendations for providers. Research suggests the publication of guidelines may not change provider behavior. This study evaluates computer assistance for implementing obesity guidelines in school-based health centers. Significant improvements in identification and assessment of obesity in children with technology support were noted. Computer decision support shows promise for promoting the implementation of current recommendations by supporting providers in identifying, assessing, and providing tailored recommendations for children at risk of obesity.

Full Waveform Modeling of Transient Electromagnetic Response Based on Temporal Interpolation and Convolution Method

NASA Astrophysics Data System (ADS)

Qi, Youzheng; Huang, Ling; Wu, Xin; Zhu, Wanhua; Fang, Guangyou; Yu, Gang

2017-07-01

Quantitative modeling of the transient electromagnetic (TEM) response requires consideration of the full transmitter waveform, i.e., not only the specific current waveform in a half cycle but also the bipolar repetition. In this paper, we present a novel temporal interpolation and convolution (TIC) method to facilitate the accurate TEM modeling. We first calculate the temporal basis response on a logarithmic scale using the fast digital-filter-based methods. Then, we introduce a function named hamlogsinc in the framework of discrete signal processing theory to reconstruct the basis function and to make the convolution with the positive half of the waveform. Finally, a superposition procedure is used to take account of the effect of previous bipolar waveforms. Comparisons with the established fast Fourier transform method demonstrate that our TIC method can get the same accuracy with a shorter computing time.

Derivation of Continuum Models from An Agent-based Cancer Model: Optimization and Sensitivity Analysis.

PubMed

Voulgarelis, Dimitrios; Velayudhan, Ajoy; Smith, Frank

2017-01-01

Agent-based models provide a formidable tool for exploring complex and emergent behaviour of biological systems as well as accurate results but with the drawback of needing a lot of computational power and time for subsequent analysis. On the other hand, equation-based models can more easily be used for complex analysis in a much shorter timescale. This paper formulates an ordinary differential equations and stochastic differential equations model to capture the behaviour of an existing agent-based model of tumour cell reprogramming and applies it to optimization of possible treatment as well as dosage sensitivity analysis. For certain values of the parameter space a close match between the equation-based and agent-based models is achieved. The need for division of labour between the two approaches is explored. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Josephson Radiation from Gapless Andreev Bound States in HgTe-Based Topological Junctions

NASA Astrophysics Data System (ADS)

Deacon, R. S.; Wiedenmann, J.; Bocquillon, E.; Domínguez, F.; Klapwijk, T. M.; Leubner, P.; Brüne, C.; Hankiewicz, E. M.; Tarucha, S.; Ishibashi, K.; Buhmann, H.; Molenkamp, L. W.

2017-04-01

Frequency analysis of the rf emission of oscillating Josephson supercurrent is a powerful passive way of probing properties of topological Josephson junctions. In particular, measurements of the Josephson emission enable the detection of topological gapless Andreev bound states that give rise to emission at half the Josephson frequency fJ rather than conventional emission at fJ. Here, we report direct measurement of rf emission spectra on Josephson junctions made of HgTe-based gate-tunable topological weak links. The emission spectra exhibit a clear signal at half the Josephson frequency fJ/2 . The linewidths of emission lines indicate a coherence time of 0.3-4 ns for the fJ/2 line, much shorter than for the fJ line (3-4 ns). These observations strongly point towards the presence of topological gapless Andreev bound states and pave the way for a future HgTe-based platform for topological quantum computation.

Sparse non-negative matrix factorizations via alternating non-negativity-constrained least squares for microarray data analysis.

PubMed

Kim, Hyunsoo; Park, Haesun

2007-06-15

Many practical pattern recognition problems require non-negativity constraints. For example, pixels in digital images and chemical concentrations in bioinformatics are non-negative. Sparse non-negative matrix factorizations (NMFs) are useful when the degree of sparseness in the non-negative basis matrix or the non-negative coefficient matrix in an NMF needs to be controlled in approximating high-dimensional data in a lower dimensional space. In this article, we introduce a novel formulation of sparse NMF and show how the new formulation leads to a convergent sparse NMF algorithm via alternating non-negativity-constrained least squares. We apply our sparse NMF algorithm to cancer-class discovery and gene expression data analysis and offer biological analysis of the results obtained. Our experimental results illustrate that the proposed sparse NMF algorithm often achieves better clustering performance with shorter computing time compared to other existing NMF algorithms. The software is available as supplementary material.

A facilitative effect of negative affective valence on working memory.

PubMed

Gotoh, Fumiko; Kikuchi, Tadashi; Olofsson, Ulrich

2010-06-01

Previous studies have shown that negatively valenced information impaired working memory performance due to an attention-capturing effect. The present study examined whether negative valence could also facilitate working memory. Affective words (negative, neutral, positive) were used as retro-cues in a working memory task that required participants to remember colors at different spatial locations on a computer screen. Following the cue, a target detection task was used to either shift attention to a different location or keep attention at the same location as the retro-cue. Finally, participants were required to discriminate the cued color from a set of distractors. It was found that negative cues yielded shorter response times (RTs) in the attention-shift condition and longer RTs in the attention-stay condition, compared with neutral and positive cues. The results suggest that negative affective valence may enhance working memory performance (RTs), provided that attention can be disengaged.

Is Virtual Surgical Planning in Orthognathic Surgery Faster Than Conventional Planning? A Time and Workflow Analysis of an Office-Based Workflow for Single- and Double-Jaw Surgery.

PubMed

Steinhuber, Thomas; Brunold, Silvia; Gärtner, Catherina; Offermanns, Vincent; Ulmer, Hanno; Ploder, Oliver

2018-02-01

The purpose of this study was to measure and compare the working time for virtual surgical planning (VSP) in orthognathic surgery in a largely office-based workflow in comparison with conventional surgical planning (CSP) regarding the type of surgery, staff involved, and working location. This prospective cohort study included patients treated with orthognathic surgery from May to December 2016. For each patient, both CSP with manual splint fabrication and VSP with fabrication of computer-aided design-computer-aided manufacturing splints were performed. The predictor variables were planning method (CSP or VSP) and type of surgery (single or double jaw), and the outcome was time. Descriptive and analytic statistics, including analysis of variance for repeated measures, were computed. The sample was composed of 40 patients (25 female and 15 male patients; mean age, 24.6 years) treated with single-jaw surgery (n = 18) or double-jaw surgery (n = 22). The mean times for planning single-jaw surgery were 145.5 ± 11.5 minutes for CSP and 109.3 ± 10.8 minutes for VSP, and those for planning double-jaw surgery were 224.1 ± 11.2 minutes and 149.6 ± 15.3 minutes, respectively. Besides the expected result that the working time was shorter for single-versus double-jaw surgery (P < .001), it was shown that VSP shortened the working time significantly versus CSP (P < .001). The reduction of time through VSP was relatively stronger for double-jaw surgery (P < .001 for interaction). All differences between CSP and VSP regarding profession (except for the surgeon's time investment) and location were statistically significant (P < .01). The surgeon's time to plan single-jaw surgery was 37.0 minutes for CSP and 41.2 minutes for VSP; for double-jaw surgery, it was 53.8 minutes and 53.6 minutes, respectively. Office-based VSP for orthognathic surgery was significantly faster for single- and double-jaw surgery. The time investment of the surgeon was equal for both methods, and all other steps of the workflow differed significantly compared with CSP. Copyright © 2017 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

Adding moxifloxacin is associated with a shorter time to culture conversion in pulmonary tuberculosis.

PubMed

Wang, J-Y; Wang, J-T; Tsai, T-H; Hsu, C-L; Yu, C-J; Hsueh, P-R; Lee, L-N; Yang, P-C

2010-01-01

To investigate whether adding moxifloxacin (MXF) to the standard anti-tuberculosis regimen can shorten the time to sputum culture conversion in pulmonary tuberculosis (PTB). Adults with culture-positive PTB were divided into two treatment groups by their choice: standard regimen alone (HERZ group) and standard regimen plus daily 400 mg MXF in the first 2 months (MXF group). Sputum samples were collected thrice weekly in the first 8 weeks. The propensity score was calculated to estimate the conditional probability of entering the MXF group. Factors influencing time to culture conversion were investigated using Cox proportional hazards regression analysis stratified by propensity score. Sixty-two patients were enrolled in the MXF group and 88 in the HERZ group; respectively 51 and 72 completed the study. The regimen was modified before culture conversion in respectively 6 (12%) and 12 (16%; P = 0.47) patients, due to adverse effects. The time to culture conversion was shorter in the MXF group (HR 2.1, 95%CI 1.4-3.2). The culture conversion rate after 6 weeks of treatment was respectively 82% and 61% (P = 0.011, <0.05/4, calculated using the modified Bonferroni method). Adding MXF to the standard anti-tuberculosis regimen in the first 2 months was associated with a shorter time to culture conversion, a higher 6-week culture conversion rate and reduced transmission of tuberculosis.

Low-energy laser in the treatment of alopecia of the scalp

NASA Astrophysics Data System (ADS)

Ciuchita, Tavi; Usurelu, Mircea; Antipa, Ciprian

1997-12-01

The authors tried to verify the efficacy of low energy laser (LEL) in scalp alopecia. Sixty patients were divided in two groups: A) laser group, 33 patients treated with both LEL and classical therapy; B) control group, 27 patients treated only with classical therapy, Before, during and after treatment, historical samples were done. For the group A the results were rather superior but in a twice shorter time shorter time than group B. The maintenance of the good results needed classical therapy for a long period. We conclude that LEL therapy could have a useful complementary method for the treatment of scalp alopecia.

Cyclical Annealing Technique To Enhance Reliability of Amorphous Metal Oxide Thin Film Transistors.

PubMed

Chen, Hong-Chih; Chang, Ting-Chang; Lai, Wei-Chih; Chen, Guan-Fu; Chen, Bo-Wei; Hung, Yu-Ju; Chang, Kuo-Jui; Cheng, Kai-Chung; Huang, Chen-Shuo; Chen, Kuo-Kuang; Lu, Hsueh-Hsing; Lin, Yu-Hsin

2018-02-26

This study introduces a cyclical annealing technique that enhances the reliability of amorphous indium-gallium-zinc-oxide (a-IGZO) via-type structure thin film transistors (TFTs). By utilizing this treatment, negative gate-bias illumination stress (NBIS)-induced instabilities can be effectively alleviated. The cyclical annealing provides several cooling steps, which are exothermic processes that can form stronger ionic bonds. An additional advantage is that the total annealing time is much shorter than when using conventional long-term annealing. With the use of cyclical annealing, the reliability of the a-IGZO can be effectively optimized, and the shorter process time can increase fabrication efficiency.

Palliation of clinical signs in 48 dogs with nasal carcinomas treated with coarse-fraction radiation therapy.

PubMed

Gieger, Tracy; Rassnick, Kenneth; Siegel, Sheri; Proulx, David; Bergman, Philip; Anderson, Christine; LaDue, Tracy; Smith, Annette; Northrup, Nicole; Roberts, Royce

2008-01-01

Data from 48 dogs with nasal carcinomas treated with palliative radiation therapy (PRT) were retrospectively reviewed. Factors potentially influencing resolution of clinical signs and survival after PRT were evaluated. Clinical signs completely resolved in 66% of dogs for a median of 120 days. The overall median survival time was 146 days. Duration of response to PRT was shorter in dogs that had clinical signs for <90 days before PRT. Survival times were shorter in dogs that had partial or no resolution of clinical signs after PRT than in dogs that had complete resolution of clinical signs.

Anterior Cervical Corpectomy with free vascularized fibular graft versus multilevel discectomy and grafting for Cervical Spondylotic Myelopathy

PubMed Central

Addosooki, Ahmad I; El-deen, Mohamed Alam

2015-01-01

Purpose A retrospective study to compare the radiologic and clinical outcomes of 2 different anterior approaches, multilevel anterior cervical discectomy with fusion (ACDF) using autologus ticortical bone graft versus anterior cervical corpectomy with fusion (ACCF) using free vascularized fibular graft (FVFG) for the management of cervical spondylotic myelopathy(CSM). Methods A total of 15 patients who underwent ACDF or ACCF using FVFG for multilevel CSM were divided into two groups. Group A (n = 7) underwent ACDF and group B (n = 8) ACCF. Clinical outcomes using Japanese Orthopaedic Association (JOA) score, perioperative parameters including operation time and hospital stay, radiological parameters including fusion rate and cervical lordosis, and complications were compared. Results Both group A and group B demonstrated significant increases in JOA scores. Patients who underwent ACDF experienced significantly shorter operation times and hospital stay. Both groups showed significant increases in postoperative cervical lordosis and achieved the same fusion rate (100 %). No major complications were encountered in both groups. Conclusion Both ACDF and ACCF using FVFG provide satisfactory clinical outcomes and fusion rates for multilevel CSM. However, multilevel ACDF is associated with better radiologic parameters, shorter hospital stay and shorter operative times. PMID:26767152

Using a Virtual Environment to Study Pedestrian Behaviors: How Does Time Pressure Affect Children's and Adults' Street Crossing Behaviors?

PubMed

Morrongiello, Barbara A; Corbett, Michael; Switzer, Jessica; Hall, Tom

2015-08-01

The aim of this study was to examine how crossing under time pressure influences the pedestrian behaviors of children and adults. Using a highly immersive virtual reality system interfaced with a 3D movement measurement system, various indices of children's and adults' crossing behaviors were measured under time-pressure and no time-pressure conditions. Pedestrians engaged in riskier crossing behaviors on time-pressure trials as indicated by appraising traffic for a shorter period before initiating their crossing, selecting shorter more hazardous temporal gaps to cross into, and having the car come closer to them (less time to spare). There were no age or sex differences in how time pressure affected crossing behaviors. The current findings indicate that, at all ages, pedestrians experience greater exposure to traffic dangers when they cross under time pressure. © The Author 2015. Published by Oxford University Press on behalf of the Society of Pediatric Psychology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Intervention on Surgical Systemic-to-Pulmonary Artery Shunts: Carotid Versus Femoral Access.

PubMed

Ligon, R Allen; Ooi, Yinn K; Kim, Dennis W; Vincent, Robert N; Petit, Christopher J

2017-09-11

The purpose of this study was to compare results between the femoral arterial (FA) and carotid arterial (CA) approaches in catheter-based interventions on Blalock-Taussig shunts (BTS). Transcatheter intervention on BTS is often performed in shunt-dependent, hypoxemic infants. The approach to BTS intervention likely has an impact on timeliness and overall success. The authors reviewed all cases of catheter intervention for BTS obstruction between 2012 and 2017 for their institution. They sought to compare procedural success rates and time, sheath time, time to arterial access, and time from access to stent implantation between FA and CA approaches. There were 42 BTS interventions between 34 patients. BTS intervention was more successful from the CA approach (p = 0.035). Among the FA cohort, BTS intervention was unsuccessful in 8 cases (25%), 5 of which were converted to CA with subsequent success. The CA cohort had lower procedure time (62 min vs. 104 min; p = 0.01) and anesthesia time (119 min vs. 151 min; p = 0.01). Additionally, CA access was associated with shorter time to arterial access (4.0 min vs. 9.3 min; p < 0.01), time to placement of the guidewire through the BTS (6.5 min vs. 13 min; p < 0.01), and time from the final sheath to BTS stent implantation (9 min vs. 20 min; p < 0.01). Operators should consider the route of access to the BTS deliberately. The authors' approach has been the carotid artery as an alternative access site-associated with greater procedural success, shorter procedural time, and shorter time to stent implantation. Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

An Ultrathin Endoscope with a 2.4-mm Working Channel Shortens the Esophagogastroduodenoscopy Time by Shortening the Suction Time

PubMed Central

Shinozaki, Satoshi; Miura, Yoshimasa; Ino, Yuji; Shinozaki, Kenjiro; Lefor, Alan Kawarai; Yamamoto, Hironori

2015-01-01

Background/Aims: Poor suction ability through a narrow working channel prolongs esophagogastroduodenoscopy (EGD). The aim of this study was to evaluate suction with a new ultrathin endoscope (EG-580NW2; Fujifilm Corp.) having a 2.4-mm working channel in clinical practice. Methods: To evaluate in vitro suction, 200 mL water was suctioned and the suction time was measured. The clinical data of 117 patients who underwent EGD were retrospectively reviewed on the basis of recorded video, and the suction time was measured by using a stopwatch. Results: In vitro, the suction time with the EG-580NW2 endoscope was significantly shorter than that with the use of an ultrathin endoscope with a 2.0-mm working channel (EG-580NW; mean ± standard deviation, 22.7±1.1 seconds vs. 34.7±2.2 seconds; p<0.001). We analyzed the total time and the suction time for routine EGD in 117 patients (50 in the EG-580NW2 group and 67 in the EG-580NW group). In the EG-580NW2 group, the total time for EGD was significantly shorter than that in the EG-580NW group (275.3±42.0 seconds vs. 300.6±46.5 seconds, p=0.003). In the EG-580NW2 group, the suction time was significantly shorter than that in the EG-580NW group (19.2±7.6 seconds vs. 38.0±15.9 seconds, p<0.001). Conclusions: An ultrathin endoscope with a 2.4-mm working channel considerably shortens the routine EGD time by shortening the suction time, in comparison with an endoscope with a 2.0-mm working channel. PMID:26668798

Effects of simulated increased gravity on the rate of aging of rats - Implications for the rate of living theory of aging

NASA Technical Reports Server (NTRS)

Economos, A. C.; Ballard, R. C.; Blunden, M.; Miquel, J.; Lindseth, K. A.; Fleming, J.; Philpott, D. E.; Oyama, J.

1982-01-01

It was found that the rate of aging of 17 month old rats which had been exposed to 3.14 times normal gravity in an animal centrifuge for 8 months was larger than that of the controls as determined by the apparently elevated lipofuscin content in heart and kidney, reduced numbers and increased size of mitochondria of heart tissue, and inferior liver mitochondria respiration. Steady-state food intake per day per kg body weight, which is presumably proportional to rate of living or specific basal metabolic expenditure, was found to be about 18 percent higher than in the controls after an initial 2 month adaptation period. Although half of the centrifuged animals lived only a little shorter than the controls (average about 343 vs. 364 days on the average, statistically nonsignificant), the remaining half (longest survivors) lived on the centrifuge an average of 520 days (range 483-572) compared to an average of 574 days (range 502-615) for the controls, computed from the onset of centrifugation, or 11 percent shorter. These findings indicate that a moderate increase of the level of basal metabolism of young adult rats adapted to hypergravity compared to controls in normal gravity is accompanied by a roughly similar increase in the rate of organ aging and reduction of survival, in agreement with Pearl's (1928) rate of living theory of aging, previously experimentally demonstrated only in poikilotherms.

Objective assessment of gender roles: Gender Roles Test (GRT-36).

PubMed

Fernández, Juan; Quiroga, M Angeles; del Olmo, Isabel; Aróztegui, Javier; Martín, Arantxa

2011-11-01

This study was designed to develop a computerized test to assess gender roles. This test is presented as a decision-making task to mask its purpose. Each item displays a picture representing an activity and a brief sentence that describes it. Participants have to choose the most suitable sex to perform each activity: man or woman. The test (Gender Roles Test, GRT-36) consists of 36 items/activities. The program registers both the choices made and their response times (RTs). Responses are considered as stereotyped when the chosen sex fits stereotyped roles and non-stereotyped when the chosen sex does not fit stereotyped roles. Individual means (RTs) were computed for stereotyped and non-stereotyped responses, differentiating between domestic and work spheres. A "D" score, reflecting the strength of association between activities and sex, was calculated for each sphere and sex. The study incorporated 78 participants (69% women and 31% men) ranging from 19 to 59 years old. The results show that: (a) reading speed does not explain the variability in the RTs; (b) RTs show good internal consistency; (c) RTs are shorter for stereotyped than for neutral stimuli; (d) RTs are shorter for stereotyped than for non-stereotyped responses. Intended goals are supported by obtained results. Scores provided by the task facilitate both group and individual detailed analysis of gender role, differentiating the gender role assigned to men from that assigned to women, at the domestic and work spheres. Obtained data fall within the scope of the genderology and their implications are discussed.

The Role of Bolus Injection of Saline with Arm Elevation on Rocuronium onset Time: A Randomized Control Study

PubMed Central

Kulkarni, Malavika; Chuchendra, L. S.; Bhavya, P. J.

2018-01-01

Background: The onset time of neuromuscular blockade is a crucial time associated with the risk of hypoxia and pulmonary aspiration. Various strategies have been undertaken to shorten this onset time. Therefore, we investigated the effects of bolus of 20 ml saline followed by limb elevation after administration of rocuronium in a dose of 0.6 mg/kg to study the onset time. Methodology: Thirty patients were randomly allocated to the bolus saline group or control group. General anesthesia was induced and maintained with fentanyl and propofol. Rocuronium 0.6 mg/kg intravenous (IV) was administered followed by 20 ml saline bolus and limb elevation in the study group compared to administration of 0.6 mg/kg in a running drip only in the control. Onset of neuromuscular block was assessed by acceleromyography at the adductor pollicis muscle with train-of-four stimulation. Results: The lag time was shorter in bolus group (34 s median) than in control group (45 s median), P < 0.017. The onset time was shorter in bolus group (55 s median) than in control group (110 s median), P < 0.001. The T1 recovery to 25% was longer in bolus group (42 min median) than in control group (39 min median) which was statistically not significant. Conclusion: Rocuronium 0.6 mg/kg IV followed by bolus 20 ml saline and concomitant limb elevation resulted in shorter lag time, faster onset of neuromuscular blockade, good intubating conditions without prolonging clinical duration of action when compared to the control. PMID:29628555

Photonic band gap materials: towards an all-optical transistor

NASA Astrophysics Data System (ADS)

Florescu, Marian

2002-05-01

The transmission of information as optical signals encoded on light waves traveling through optical fibers and optical networks is increasingly moving to shorter and shorter distance scales. In the near future, optical networking is poised to supersede conventional transmission over electric wires and electronic networks for computer-to-computer communications, chip-to-chip communications, and even on-chip communications. The ever-increasing demand for faster and more reliable devices to process the optical signals offers new opportunities in developing all-optical signal processing systems (systems in which one optical signal controls another, thereby adding "intelligence" to the optical networks). All-optical switches, two-state and many-state all-optical memories, all-optical limiters, all-optical discriminators and all-optical transistors are only a few of the many devices proposed during the last two decades. The "all-optical" label is commonly used to distinguish the devices that do not involve dissipative electronic transport and require essentially no electrical communication of information. The all-optical transistor action was first observed in the context of optical bistability [1] and consists in a strong differential gain regime, in which, for small variations in the input intensity, the output intensity has a very strong variation. This analog operation is for all-optical input what transistor action is for electrical inputs.

Independence of reaction time and response force control during isometric leg extension.

PubMed

Fukushi, Tamami; Ohtsuki, Tatsuyuki

2004-04-01

In this study, we examined the relative control of reaction time and force in responses of the lower limb. Fourteen female participants (age 21.2 +/- 1.0 years, height 1.62 +/- 0.05 m, body mass 54.1 +/- 6.1 kg; mean +/- s) were instructed to exert their maximal isometric one-leg extension force as quickly as possible in response to an auditory stimulus presented after one of 13 foreperiod durations, ranging from 0.5 to 10.0 s. In the 'irregular condition' each foreperiod was presented in random order, while in the 'regular condition' each foreperiod was repeated consecutively. A significant interactive effect of foreperiod duration and regularity on reaction time was observed (P < 0.001 in two-way ANOVA with repeated measures). In the irregular condition the shorter foreperiod induced a longer reaction time, while in the regular condition the shorter foreperiod induced a shorter reaction time. Peak amplitude of isometric force was affected only by the regularity of foreperiod and there was a significant variation of changes in peak force across participants; nine participants were shown to significantly increase peak force for the regular condition (P < 0.001), three to decrease it (P < 0.05) and two showed no difference. These results indicate the independence of reaction time and response force control in the lower limb motor system. Variation of changes in peak force across participants may be due to the different attention to the bipolar nature of the task requirements such as maximal force and maximal speed.

Predicting the time of conversion to MCI in the elderly: role of verbal expression and learning.

PubMed

Oulhaj, Abderrahim; Wilcock, Gordon K; Smith, A David; de Jager, Celeste A

2009-11-03

Increasing awareness that minimal or mild cognitive impairment (MCI) in the elderly may be a precursor of dementia has led to an increase in the number of people attending memory clinics. We aimed to develop a way of predicting the period of time before cognitive impairment occurs in community-dwelling elderly. The method is illustrated by the use of simple tests of different cognitive domains. A cohort of 241 normal elderly volunteers was followed for up to 20 years with regular assessments of cognitive abilities using the Cambridge Cognitive Examination (CAMCOG); 91 participants developed MCI. We used interval-censored survival analysis statistical methods to model which baseline cognitive tests best predicted the time to convert to MCI. Out of several baseline variables, only age and CAMCOG subscores for expression and learning/memory were predictors of the time to conversion. The time to conversion was 14% shorter for each 5 years of age, 17% shorter for each point lower in the expression score, and 15% shorter for each point lower in the learning score. We present in tabular form the probability of converting to MCI over intervals between 2 and 10 years for different combinations of expression and learning scores. In apparently normal elderly people, subtle measurable cognitive deficits that occur within the normal range on standard testing protocols reliably predict the time to clinically relevant cognitive impairment long before clinical symptoms are reported.

2D projection-based software application for mobile C-arms optimises wire placement in the proximal femur - An experimental study.

PubMed

Swartman, B; Frere, D; Wei, W; Schnetzke, M; Beisemann, N; Keil, H; Franke, J; Grützner, P A; Vetter, S Y

2017-10-01

A new software application can be used without fixed reference markers or a registration process in wire placement. The aim was to compare placement of Kirschner wires (K-wires) into the proximal femur with the software application versus the conventional method without guiding. As study hypothesis, we assumed less placement attempts, shorter procedure time and shorter fluoroscopy time using the software. The same precision inside a proximal femur bone model using the software application was premised. The software detects a K-wire within the 2D fluoroscopic image. By evaluating its direction and tip location, it superimposes a trajectory on the image, visualizing the intended direction of the K-wire. The K-wire was positioned in 20 artificial bones with the use of software by one surgeon; 20 bones served as conventional controls. A brass thumb tack was placed into the femoral head and its tip targeted with the wire. Number of placement attempts, duration of the procedure, duration of fluoroscopy time and distance to the target in a postoperative 3D scan were recorded. Compared with the conventional method, use of the application showed fewer attempts for optimal wire placement (p=0.026), shorter duration of surgery (p=0.004), shorter fluoroscopy time (p=0.024) and higher precision (p=0.018). Final wire position was achieved in the first attempt in 17 out of 20 cases with the software and in 9 out of 20 cases with the conventional method. The study hypothesis was confirmed. The new application optimised the process of K-wire placement in the proximal femur in an artificial bone model while also improving precision. Benefits lie especially in the reduction of placement attempts and reduction of fluoroscopy time under the aspect of radiation protection. The software runs on a conventional image intensifier and can therefore be easily integrated into the daily surgical routine. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effects of solar radiation on the orbits of small particles

NASA Technical Reports Server (NTRS)

Lyttleton, R. A.

1976-01-01

A modification of the Robertson (1937) equations of particle motion in the presence of solar radiation is developed which allows for partial reflection of sunlight as a result of rapid and varying particle rotations caused by interaction with the solar wind. The coefficients and forces in earlier forms of the equations are compared with those in the present equations, and secular rates of change of particle orbital elements are determined. Orbital dimensions are calculated in terms of time, probable sizes and densities of meteoric and cometary particles are estimated, and times of infall to the sun are computed for a particle moving in an almost circular orbit and a particle moving in an elliptical orbit of high eccentricity. Changes in orbital elements are also determined for particles from a long-period sun-grazing comet. The results show that the time of infall to the sun from a highly eccentric orbit is substantially shorter than from a circular orbit with a radius equal to the mean distance in the eccentric orbit. The possibility is considered that the free orbital kinetic energy of particles drawn into the sun may be the energy source for the solar corona.

Direct Measurements of Smartphone Screen-Time: Relationships with Demographics and Sleep.

PubMed

Christensen, Matthew A; Bettencourt, Laura; Kaye, Leanne; Moturu, Sai T; Nguyen, Kaylin T; Olgin, Jeffrey E; Pletcher, Mark J; Marcus, Gregory M

2016-01-01

Smartphones are increasingly integrated into everyday life, but frequency of use has not yet been objectively measured and compared to demographics, health information, and in particular, sleep quality. The aim of this study was to characterize smartphone use by measuring screen-time directly, determine factors that are associated with increased screen-time, and to test the hypothesis that increased screen-time is associated with poor sleep. We performed a cross-sectional analysis in a subset of 653 participants enrolled in the Health eHeart Study, an internet-based longitudinal cohort study open to any interested adult (≥ 18 years). Smartphone screen-time (the number of minutes in each hour the screen was on) was measured continuously via smartphone application. For each participant, total and average screen-time were computed over 30-day windows. Average screen-time specifically during self-reported bedtime hours and sleeping period was also computed. Demographics, medical information, and sleep habits (Pittsburgh Sleep Quality Index-PSQI) were obtained by survey. Linear regression was used to obtain effect estimates. Total screen-time over 30 days was a median 38.4 hours (IQR 21.4 to 61.3) and average screen-time over 30 days was a median 3.7 minutes per hour (IQR 2.2 to 5.5). Younger age, self-reported race/ethnicity of Black and "Other" were associated with longer average screen-time after adjustment for potential confounders. Longer average screen-time was associated with shorter sleep duration and worse sleep-efficiency. Longer average screen-times during bedtime and the sleeping period were associated with poor sleep quality, decreased sleep efficiency, and longer sleep onset latency. These findings on actual smartphone screen-time build upon prior work based on self-report and confirm that adults spend a substantial amount of time using their smartphones. Screen-time differs across age and race, but is similar across socio-economic strata suggesting that cultural factors may drive smartphone use. Screen-time is associated with poor sleep. These findings cannot support conclusions on causation. Effect-cause remains a possibility: poor sleep may lead to increased screen-time. However, exposure to smartphone screens, particularly around bedtime, may negatively impact sleep.

Efficient Nash Equilibrium Resource Allocation Based on Game Theory Mechanism in Cloud Computing by Using Auction

PubMed Central

Nezarat, Amin; Dastghaibifard, GH

2015-01-01

One of the most complex issues in the cloud computing environment is the problem of resource allocation so that, on one hand, the cloud provider expects the most profitability and, on the other hand, users also expect to have the best resources at their disposal considering the budget constraints and time. In most previous work conducted, heuristic and evolutionary approaches have been used to solve this problem. Nevertheless, since the nature of this environment is based on economic methods, using such methods can decrease response time and reducing the complexity of the problem. In this paper, an auction-based method is proposed which determines the auction winner by applying game theory mechanism and holding a repetitive game with incomplete information in a non-cooperative environment. In this method, users calculate suitable price bid with their objective function during several round and repetitions and send it to the auctioneer; and the auctioneer chooses the winning player based the suggested utility function. In the proposed method, the end point of the game is the Nash equilibrium point where players are no longer inclined to alter their bid for that resource and the final bid also satisfies the auctioneer’s utility function. To prove the response space convexity, the Lagrange method is used and the proposed model is simulated in the cloudsim and the results are compared with previous work. At the end, it is concluded that this method converges to a response in a shorter time, provides the lowest service level agreement violations and the most utility to the provider. PMID:26431035

Efficient Nash Equilibrium Resource Allocation Based on Game Theory Mechanism in Cloud Computing by Using Auction.

PubMed

Nezarat, Amin; Dastghaibifard, G H

2015-01-01

One of the most complex issues in the cloud computing environment is the problem of resource allocation so that, on one hand, the cloud provider expects the most profitability and, on the other hand, users also expect to have the best resources at their disposal considering the budget constraints and time. In most previous work conducted, heuristic and evolutionary approaches have been used to solve this problem. Nevertheless, since the nature of this environment is based on economic methods, using such methods can decrease response time and reducing the complexity of the problem. In this paper, an auction-based method is proposed which determines the auction winner by applying game theory mechanism and holding a repetitive game with incomplete information in a non-cooperative environment. In this method, users calculate suitable price bid with their objective function during several round and repetitions and send it to the auctioneer; and the auctioneer chooses the winning player based the suggested utility function. In the proposed method, the end point of the game is the Nash equilibrium point where players are no longer inclined to alter their bid for that resource and the final bid also satisfies the auctioneer's utility function. To prove the response space convexity, the Lagrange method is used and the proposed model is simulated in the cloudsim and the results are compared with previous work. At the end, it is concluded that this method converges to a response in a shorter time, provides the lowest service level agreement violations and the most utility to the provider.

Cranioplasty prosthesis manufacturing based on reverse engineering technology

PubMed Central

Chrzan, Robert; Urbanik, Andrzej; Karbowski, Krzysztof; Moskała, Marek; Polak, Jarosław; Pyrich, Marek

2012-01-01

Summary Background Most patients with large focal skull bone loss after craniectomy are referred for cranioplasty. Reverse engineering is a technology which creates a computer-aided design (CAD) model of a real structure. Rapid prototyping is a technology which produces physical objects from virtual CAD models. The aim of this study was to assess the clinical usefulness of these technologies in cranioplasty prosthesis manufacturing. Material/Methods CT was performed on 19 patients with focal skull bone loss after craniectomy, using a dedicated protocol. A material model of skull deficit was produced using computer numerical control (CNC) milling, and individually pre-operatively adjusted polypropylene-polyester prosthesis was prepared. In a control group of 20 patients a prosthesis was manually adjusted to each patient by a neurosurgeon during surgery, without using CT-based reverse engineering/rapid prototyping. In each case, the prosthesis was implanted into the patient. The mean operating times in both groups were compared. Results In the group of patients with reverse engineering/rapid prototyping-based cranioplasty, the mean operating time was shorter (120.3 min) compared to that in the control group (136.5 min). The neurosurgeons found the new technology particularly useful in more complicated bone deficits with different curvatures in various planes. Conclusions Reverse engineering and rapid prototyping may reduce the time needed for cranioplasty neurosurgery and improve the prosthesis fitting. Such technologies may utilize data obtained by commonly used spiral CT scanners. The manufacturing of individually adjusted prostheses should be commonly used in patients planned for cranioplasty with synthetic material. PMID:22207125

Quasi-elastic light scattering: Signal storage, correlation, and spectrum analysis under control of an 8-bit microprocessor

NASA Astrophysics Data System (ADS)

Glatter, Otto; Fuchs, Heribert; Jorde, Christian; Eigner, Wolf-Dieter

1987-03-01

The microprocessor of an 8-bit PC system is used as a central control unit for the acquisition and evaluation of data from quasi-elastic light scattering experiments. Data are sampled with a width of 8 bits under control of the CPU. This limits the minimum sample time to 20 μs. Shorter sample times would need a direct memory access channel. The 8-bit CPU can address a 64-kbyte RAM without additional paging. Up to 49 000 sample points can be measured without interruption. After storage, a correlation function or a power spectrum can be calculated from such a primary data set. Furthermore access is provided to the primary data for stability control, statistical tests, and for comparison of different evaluation methods for the same experiment. A detailed analysis of the signal (histogram) and of the effect of overflows is possible and shows that the number of pulses but not the number of overflows determines the error in the result. The correlation function can be computed with reasonable accuracy from data with a mean pulse rate greater than one, the power spectrum needs a three times higher pulse rate for convergence. The statistical accuracy of the results from 49 000 sample points is of the order of a few percent. Additional averages are necessary to improve their quality. The hardware extensions for the PC system are inexpensive. The main disadvantage of the present system is the high minimum sampling time of 20 μs and the fact that the correlogram or the power spectrum cannot be computed on-line as it can be done with hardware correlators or spectrum analyzers. These shortcomings and the storage size restrictions can be removed with a faster 16/32-bit CPU.

Temporal resolution measurement of 128-slice dual source and 320-row area detector computed tomography scanners in helical acquisition mode using the impulse method.

PubMed

Hara, Takanori; Urikura, Atsushi; Ichikawa, Katsuhiro; Hoshino, Takashi; Nishimaru, Eiji; Niwa, Shinji

2016-04-01

To analyse the temporal resolution (TR) of modern computed tomography (CT) scanners using the impulse method, and assess the actual maximum TR at respective helical acquisition modes. To assess the actual TR of helical acquisition modes of a 128-slice dual source CT (DSCT) scanner and a 320-row area detector CT (ADCT) scanner, we assessed the TRs of various acquisition combinations of a pitch factor (P) and gantry rotation time (R). The TR of the helical acquisition modes for the 128-slice DSCT scanner continuously improved with a shorter gantry rotation time and greater pitch factor. However, for the 320-row ADCT scanner, the TR with a pitch factor of <1.0 was almost equal to the gantry rotation time, whereas with pitch factor of >1.0, it was approximately one half of the gantry rotation time. The maximum TR values of single- and dual-source helical acquisition modes for the 128-slice DSCT scanner were 0.138 (R/P=0.285/1.5) and 0.074s (R/P=0.285/3.2), and the maximum TR values of the 64×0.5- and 160×0.5-mm detector configurations of the helical acquisition modes for the 320-row ADCT scanner were 0.120 (R/P=0.275/1.375) and 0.195s (R/P=0.3/0.6), respectively. Because the TR of a CT scanner is not accurately depicted in the specifications of the individual scanner, appropriate acquisition conditions should be determined based on the actual TR measurement. Copyright © 2016 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

A real-time moment-tensor inversion system (GRiD-MT-3D) using 3-D Green's functions

NASA Astrophysics Data System (ADS)

Nagao, A.; Furumura, T.; Tsuruoka, H.

2016-12-01

We developed a real-time moment-tensor inversion system using 3-D Green's functions (GRiD-MT-3D) by improving the current system (GRiD-MT; Tsuruoka et al., 2009), which uses 1-D Green's functions for longer periods than 20 s. Our moment-tensor inversion is applied to the real-time monitoring of earthquakes occurring beneath Kanto basin area. The basin, which is constituted of thick sediment layers, lies on the complex subduction of the Philippine-Sea Plate and the Pacific Plate that can significantly affect the seismic wave propagation. We compute 3-D Green's functions using finite-difference-method (FDM) simulations considering a 3-D velocity model, which is based on the Japan Integrated Velocity Structure Model (Koketsu et al., 2012), that includes crust, mantle, and subducting plates. The 3-D FDM simulations are computed over a volume of 468 km by 432 km by 120 km in the EW, NS, and depth directions, respectively, that is discretized into 0.25 km grids. Considering that the minimum S wave velocity of the sedimentary layer is 0.5 km/s, simulations can compute seismograms up to 0.5 Hz. We calculate Green's functions between 24,700 sources, which are distributed every 0.1° in the horizontal direction and every 9 km in depth direction, and 13 F-net stations. To compute this large number of Green's functions, we used the EIC parallel computer of ERI. The reciprocity theory, which switches the source and station positions, is used to reduce total computation costs. It took 156 hours to compute all the Green's functions. Results show that at long-periods (T>15 s), only small differences are observed between the 3-D and 1-D Green's functions as indicated by high correlation coefficients of 0.9 between the waveforms. However, at shorter periods (T<10 s), the differences become larger and the correlation coefficients drop to 0.5. The effect of the 3-D heterogeneous structure especially affects the Green's functions for the ray paths that across complex geological structures, such as the sedimentary basin or the subducting plates. After incorporation of the 3-D Green's functions in the GRiD-MT-3D system, we compare the results to the former GRiD-MT system to demonstrate the effectiveness of the new system in terms of variance reduction and accuracy of the moment-tensor estimation for much smaller events than the current one.

Exercise to improve sleep in insomnia: exploration of the bidirectional effects.

PubMed

Baron, Kelly Glazer; Reid, Kathryn J; Zee, Phyllis C

2013-08-15

Exercise improves sleep quality, mood, and quality of life among older adults with insomnia. The purpose of the study was to evaluate the daily bidirectional relationships between exercise and sleep in a sample of women with insomnia. Participants included 11 women (age M = 61.27, SD 4.15) with insomnia who engaged in 30 min of aerobic exercise 3 times per week. Self-reported sleep quality was assessed at baseline and at 16 weeks. Sleep and exercise logs and wrist activity were collected continuously. Sleep variables included subjective sleep quality and objective measures recorded via wrist actigraphy (sleep onset latency [SOL], total sleep time [TST], sleep efficiency [SE], wake after sleep onset [WASO], and fragmentation index [FI]). Age, subjective sleep quality, TST, SOL, and physical fitness at baseline were tested as moderators of the daily effects. TST, SE, and self-reported global sleep quality improved from baseline to 16 weeks (p values < 0.05). Baseline ratings of sleepiness were negatively correlated with exercise session duration (p < 0.05). Daily exercise was not associated with subjective or objective sleep variables during the corresponding night. However, participants had shorter exercise duration following nights with longer SOL (p < 0.05). TST at baseline moderated the daily relationship between TST and next day exercise duration (p < 0.05). The relationship between shorter TST and shorter next day exercise was stronger in participants who had shorter TST at baseline. Results suggest that sleep influences next day exercise rather than exercise influencing sleep. The relationship between TST and next day exercise was stronger for those with shorter TST at baseline. These results suggest that improving sleep may encourage exercise participation.

Surgical team composition has a major impact on effectiveness and costs in laparoscopic donor nephrectomy.

PubMed

Özdemir-van Brunschot, Denise M D; Warlé, Michiel C; van der Jagt, Michel F; Grutters, Janneke P C; van Horne, Sharon B C E; Kloke, Heinrich J; van der Vliet, Johannes A; Langenhuijsen, Johan F; d'Ancona, Frank C

2015-05-01

Limited evidence exists that optimization of surgical team composition may improve effectiveness of laparoscopic donor nephrectomy (LDN). A retrospective cohort study with 541 consecutive LDNs. From 2003 to 2012, surgical team composition was gradually optimized with regard to the surgeons' experience, proficient assistance and the use of fixed teams. Multivariable analysis showed that a surgical team with an experienced surgeon had a significantly shorter operation time (OT) (-18 min, 95% CI -28 to -9), less estimated blood loss (EBL) (-64 mL, 95% CI -108 to -19) and shorter length of stay (LOS) (-1 day, 95% CI -1.6 to 0). Proficient assistance was also independently associated with a shorter OT (-43 min, 95% CI -53 to -33) and reduced EBL (-58 mL, 95% CI -109 to -6), whereas those procedures performed by fixed teams were related to a shorter operation (-50 min, 95% CI -59 to -43) and warm ischemia time (-1.8, 95% CI -2.1 to -1.5), a reduced mean complication grade (-0.14 per patient, 95% CI -0.3 to -0.02) and a shorter LOS (-1.1 day, 95% CI -1.7 to -05). Health care costs for LDN by one staff surgeon with unproficient assistance were 7.707 Euro, whereas costs for LDN by two staff surgeons in fixed teams were 5.614 Euro. Surgical team composition has a major impact on variables that reflect the effectiveness of LDN from the donors' perspective. Health care costs are lower for LDNs performed by two experienced surgeons in fixed team composition. We advocate the use of two experienced surgeons in fixed team composition for LDN.

Applying Agrep to r-NSA to solve multiple sequences approximate matching.

PubMed

Ni, Bing; Wong, Man-Hon; Lam, Chi-Fai David; Leung, Kwong-Sak

2014-01-01

This paper addresses the approximate matching problem in a database consisting of multiple DNA sequences, where the proposed approach applies Agrep to a new truncated suffix array, r-NSA. The construction time of the structure is linear to the database size, and the computations of indexing a substring in the structure are constant. The number of characters processed in applying Agrep is analysed theoretically, and the theoretical upper-bound can approximate closely the empirical number of characters, which is obtained through enumerating the characters in the actual structure built. Experiments are carried out using (synthetic) random DNA sequences, as well as (real) genome sequences including Hepatitis-B Virus and X-chromosome. Experimental results show that, compared to the straight-forward approach that applies Agrep to multiple sequences individually, the proposed approach solves the matching problem in much shorter time. The speed-up of our approach depends on the sequence patterns, and for highly similar homologous genome sequences, which are the common cases in real-life genomes, it can be up to several orders of magnitude.

Local order and crystallization of dense polydisperse hard spheres

NASA Astrophysics Data System (ADS)

Coslovich, Daniele; Ozawa, Misaki; Berthier, Ludovic

2018-04-01

Computer simulations give precious insight into the microscopic behavior of supercooled liquids and glasses, but their typical time scales are orders of magnitude shorter than the experimentally relevant ones. We recently closed this gap for a class of models of size polydisperse fluids, which we successfully equilibrate beyond laboratory time scales by means of the swap Monte Carlo algorithm. In this contribution, we study the interplay between compositional and geometric local orders in a model of polydisperse hard spheres equilibrated with this algorithm. Local compositional order has a weak state dependence, while local geometric order associated to icosahedral arrangements grows more markedly but only at very high density. We quantify the correlation lengths and the degree of sphericity associated to icosahedral structures and compare these results to those for the Wahnström Lennard-Jones mixture. Finally, we analyze the structure of very dense samples that partially crystallized following a pattern incompatible with conventional fractionation scenarios. The crystal structure has the symmetry of aluminum diboride and involves a subset of small and large particles with size ratio approximately equal to 0.5.

Deep Convolutional Extreme Learning Machine and Its Application in Handwritten Digit Classification

PubMed Central

Yang, Xinyi

2016-01-01

In recent years, some deep learning methods have been developed and applied to image classification applications, such as convolutional neuron network (CNN) and deep belief network (DBN). However they are suffering from some problems like local minima, slow convergence rate, and intensive human intervention. In this paper, we propose a rapid learning method, namely, deep convolutional extreme learning machine (DC-ELM), which combines the power of CNN and fast training of ELM. It uses multiple alternate convolution layers and pooling layers to effectively abstract high level features from input images. Then the abstracted features are fed to an ELM classifier, which leads to better generalization performance with faster learning speed. DC-ELM also introduces stochastic pooling in the last hidden layer to reduce dimensionality of features greatly, thus saving much training time and computation resources. We systematically evaluated the performance of DC-ELM on two handwritten digit data sets: MNIST and USPS. Experimental results show that our method achieved better testing accuracy with significantly shorter training time in comparison with deep learning methods and other ELM methods. PMID:27610128

A new method to optimize natural convection heat sinks

NASA Astrophysics Data System (ADS)

Lampio, K.; Karvinen, R.

2017-08-01

The performance of a heat sink cooled by natural convection is strongly affected by its geometry, because buoyancy creates flow. Our model utilizes analytical results of forced flow and convection, and only conduction in a solid, i.e., the base plate and fins, is solved numerically. Sufficient accuracy for calculating maximum temperatures in practical applications is proved by comparing the results of our model with some simple analytical and computational fluid dynamics (CFD) solutions. An essential advantage of our model is that it cuts down on calculation CPU time by many orders of magnitude compared with CFD. The shorter calculation time makes our model well suited for multi-objective optimization, which is the best choice for improving heat sink geometry, because many geometrical parameters with opposite effects influence the thermal behavior. In multi-objective optimization, optimal locations of components and optimal dimensions of the fin array can be found by simultaneously minimizing the heat sink maximum temperature, size, and mass. This paper presents the principles of the particle swarm optimization (PSO) algorithm and applies it as a basis for optimizing existing heat sinks.

Deep Convolutional Extreme Learning Machine and Its Application in Handwritten Digit Classification.

PubMed

Pang, Shan; Yang, Xinyi

2016-01-01

In recent years, some deep learning methods have been developed and applied to image classification applications, such as convolutional neuron network (CNN) and deep belief network (DBN). However they are suffering from some problems like local minima, slow convergence rate, and intensive human intervention. In this paper, we propose a rapid learning method, namely, deep convolutional extreme learning machine (DC-ELM), which combines the power of CNN and fast training of ELM. It uses multiple alternate convolution layers and pooling layers to effectively abstract high level features from input images. Then the abstracted features are fed to an ELM classifier, which leads to better generalization performance with faster learning speed. DC-ELM also introduces stochastic pooling in the last hidden layer to reduce dimensionality of features greatly, thus saving much training time and computation resources. We systematically evaluated the performance of DC-ELM on two handwritten digit data sets: MNIST and USPS. Experimental results show that our method achieved better testing accuracy with significantly shorter training time in comparison with deep learning methods and other ELM methods.

An optimized treatment for algorithmic differentiation of an important glaciological fixed-point problem

DOE PAGES

Goldberg, Daniel N.; Narayanan, Sri Hari Krishna; Hascoet, Laurent; ...

2016-05-20

We apply an optimized method to the adjoint generation of a time-evolving land ice model through algorithmic differentiation (AD). The optimization involves a special treatment of the fixed-point iteration required to solve the nonlinear stress balance, which differs from a straightforward application of AD software, and leads to smaller memory requirements and in some cases shorter computation times of the adjoint. The optimization is done via implementation of the algorithm of Christianson (1994) for reverse accumulation of fixed-point problems, with the AD tool OpenAD. For test problems, the optimized adjoint is shown to have far lower memory requirements, potentially enablingmore » larger problem sizes on memory-limited machines. In the case of the land ice model, implementation of the algorithm allows further optimization by having the adjoint model solve a sequence of linear systems with identical (as opposed to varying) matrices, greatly improving performance. Finally, the methods introduced here will be of value to other efforts applying AD tools to ice models, particularly ones which solve a hybrid shallow ice/shallow shelf approximation to the Stokes equations.« less

Effect of gum chewing on reducing postoperative ileus and recovery after colorectal surgery: A randomised controlled trial.

PubMed

Topcu, Sacide Yildizeli; Oztekin, Seher Deniz

2016-05-01

This study aimed to determine the effect of gum chewing on the reduction of postoperative ileus and recovery after surgery. This study was conducted a randomized controlled trial in 60 patients who underwent colorectal surgery between November 2011 and December 2012. Patients in the experimental group chewed gum three times a day. The time of flatus and defecation, the time to start feeding, pain levels and time of discharge were monitored. Post-surgery results for gum-chewing were first flatus and defecation times and the time to start feeding was shorter; pain levels were lower on the 3rd - 5th days; patients were discharged in a shorter time post-surgery. Chewing gum is a simple intervention for reducing postoperative ileus after colorectal surgery. Further studies that examine the effectiveness of gum chewing on other surgical interventions in which the development risk of postoperative ileus should be performed. Copyright © 2016 Elsevier Ltd. All rights reserved.

Evaluation of arm-leg coordination in flat breaststroke.

PubMed

Chollet, D; Seifert, L; Leblanc, H; Boulesteix, L; Carter, M

2004-10-01

This study proposes a new method to evaluate arm-leg coordination in flat breaststroke. Five arm and leg stroke phases were defined with a velocity-video system. Five time gaps quantified the time between arm and leg actions during three paces of a race (200 m, 100 m and 50 m) in 16 top level swimmers. Based on these time gaps, effective glide, effective propulsion, effective leg insweep and effective recovery were used to identify the different stroke phases of the body. A faster pace corresponded to increased stroke rate, decreased stroke length, increased propulsive phases, shorter glide phases, and a shorter T1 time gap, which measured the effective body glide. The top level swimmers showed short time gaps (T2, T3, T4, measuring the timing of arm-leg recoveries), which reflected the continuity in arm and leg actions. The measurement of these time gaps thus provides a pertinent evaluation of swimmers' skill in adapting their arm-leg coordination to biomechanical constraints.

Quantum to classical transition in quantum field theory

NASA Astrophysics Data System (ADS)

Lombardo, Fernando C.

1998-12-01

We study the quatum to classical transition process in the context of quantum field theory. Extending the influence functional formalism of Feynman and Vernon, we study the decoherence process for self-interacting quantum fields in flat space. We also use this formalism for arbitrary geometries to analyze the quantum to classical transition in quantum gravity. After summarizing the main results known for the quantum Brownian motion, we consider a self-interacting field theory in Minkowski spacetime. We compute a coarse grained effective action by integrating out the field modes with wavelength shorter than a critical value. From this effective action we obtain the evolution equation for the reduced density matrix (master equation). We compute the diffusion coefficients for this equation and analyze the decoherence induced on the long-wavelength modes. We generalize the results to the case of a conformally coupled scalar field in de Sitter spacetime. We show that the decoherence is effective as long as the critical wavelength is taken to be not shorter than the Hubble radius. On the other hand, we study the classical limit for scalar-tensorial models in two dimensions. We consider different couplings between the dilaton and the scalar field. We discuss the Hawking radiation process and, from an exact evaluation of the influence functional, we study the conditions by which decoherence ensures the validity of the semiclassical approximation in cosmological metrics. Finally we consider four dimensional models with massive scalar fields, arbitrary coupled to the geometry. We compute the Einstein-Langevin equations in order to study the effect of the fluctuations induced by the quantum fields on the classical geometry.

Rapid Tsunami Inundation Forecast from Near-field or Far-field Earthquakes using Pre-computed Tsunami Database: Pelabuhan Ratu, Indonesia

NASA Astrophysics Data System (ADS)

Gusman, A. R.; Setiyono, U.; Satake, K.; Fujii, Y.

2017-12-01

We built pre-computed tsunami inundation database in Pelabuhan Ratu, one of tsunami-prone areas on the southern coast of Java, Indonesia. The tsunami database can be employed for a rapid estimation of tsunami inundation during an event. The pre-computed tsunami waveforms and inundations are from a total of 340 scenarios ranging from 7.5 to 9.2 in moment magnitude scale (Mw), including simple fault models of 208 thrust faults and 44 tsunami earthquakes on the plate interface, as well as 44 normal faults and 44 reverse faults in the outer-rise region. Using our tsunami inundation forecasting algorithm (NearTIF), we could rapidly estimate the tsunami inundation in Pelabuhan Ratu for three different hypothetical earthquakes. The first hypothetical earthquake is a megathrust earthquake type (Mw 9.0) offshore Sumatra which is about 600 km from Pelabuhan Ratu to represent a worst-case event in the far-field. The second hypothetical earthquake (Mw 8.5) is based on a slip deficit rate estimation from geodetic measurements and represents a most likely large event near Pelabuhan Ratu. The third hypothetical earthquake is a tsunami earthquake type (Mw 8.1) which often occur south off Java. We compared the tsunami inundation maps produced by the NearTIF algorithm with results of direct forward inundation modeling for the hypothetical earthquakes. The tsunami inundation maps produced from both methods are similar for the three cases. However, the tsunami inundation map from the inundation database can be obtained in much shorter time (1 min) than the one from a forward inundation modeling (40 min). These indicate that the NearTIF algorithm based on pre-computed inundation database is reliable and useful for tsunami warning purposes. This study also demonstrates that the NearTIF algorithm can work well even though the earthquake source is located outside the area of fault model database because it uses a time shifting procedure for the best-fit scenario searching.

Collaborative Interventions Reduce Time-to-Thrombolysis for Acute Ischemic Stroke in a Public Safety Net Hospital.

PubMed

Threlkeld, Zachary D; Kozak, Benjamin; McCoy, David; Cole, Sara; Martin, Christine; Singh, Vineeta

2017-07-01

Shorter time-to-thrombolysis in acute ischemic stroke (AIS) is associated with improved functional outcome and reduced morbidity. We evaluate the effect of several interventions to reduce time-to-thrombolysis at an urban, public safety net hospital. All patients treated with tissue plasminogen activator for AIS at our institution between 2008 and 2015 were included in a retrospective analysis of door-to-needle (DTN) time and associated factors. Between 2011 and 2014, we implemented 11 distinct interventions to reduce DTN time. Here, we assess the relative impact of each intervention on DTN time. The median DTN time pre- and postintervention decreased from 87 (interquartile range: 68-109) minutes to 49 (interquartile range: 39-63) minutes. The reduction was comprised primarily of a decrease in median time from computed tomography scan order to interpretation. The goal DTN time of 60 minutes or less was achieved in 9% (95% confidence interval: 5%-22%) of cases preintervention, compared with 70% (58%-81%) postintervention. Interventions with the greatest impact on DTN time included the implementation of a stroke group paging system, dedicated emergency department stroke pharmacists, and the development of a stroke code supply box. Multidisciplinary, collaborative interventions are associated with a significant and substantial reduction in time-to-thrombolysis. Such targeted interventions are efficient and achievable in resource-limited settings, where they are most needed. Copyright © 2017 National Stroke Association. Published by Elsevier Inc. All rights reserved.

EFFECTS OF LONG-TIME COMMUTING AND LONG-HOUR WORKING ON LIFESTYLE AND MENTAL HEALTH AMONG SCHOOL TEACHERS IN TOKYO, JAPAN.

PubMed

Nomoto, Marino; Hara, Akiko; Kikuchi, Kimiyo

2015-06-01

The objective of this study was to investigate the effects of long-time commuting and long-hour working on lifestyle including sleeping, physical exercise, breakfast, smoking, alcohol intake and mental health. In this cross-sectional study, data were collected from 146 school teachers in Tokyo. The binary associations of commuting time and working hours with lifestyle, mental stress measured by the General Health Questionnaire (GHQ) and stress coping measured by the Sense of Coherence (SOC) scores were examined. The Chi-square test was used for statistical analyses. Our results indicated that the mean commuting time and working hours per week of the respondents were 42.1 (SD 22.5) minutes and 50.4 (SD 8.6) hours, respectively. Longer commuting time was significantly associated with shorter working hours (p = 0.023), less physical exercise (p < 0.001) and shorter sleeping hours (p = 0.001). Longer working hours were significantly associated with more frequent working on holidays (p = 0.001), higher SOC scores (p = 0.001) and more smoking (p = 0.028). The negative association between GHQ and SOC scores was also significant (p < 0.001). Our findings revealed that long-time commuters were more likely to sleep less, exercise less and work less long. Long-hour workers were more likely to commute shorter, work on holidays more frequently, smoke more and their stress coping potentials were higher. Some kinds of strategies are required to improve the healthy lifestyle for long-time com- muters or long-hour workers. Key words: stress; stress coping; general health questionnaire; sense of coherence

The Ionic Atmosphere around A-RNA: Poisson-Boltzmann and Molecular Dynamics Simulations

PubMed Central

Kirmizialtin, Serdal; Silalahi, Alexander R.J.; Elber, Ron; Fenley, Marcia O.

2012-01-01

The distributions of different cations around A-RNA are computed by Poisson-Boltzmann (PB) equation and replica exchange molecular dynamics (MD). Both the nonlinear PB and size-modified PB theories are considered. The number of ions bound to A-RNA, which can be measured experimentally, is well reproduced in all methods. On the other hand, the radial ion distribution profiles show differences between MD and PB. We showed that PB results are sensitive to ion size and functional form of the solvent dielectric region but not the solvent dielectric boundary definition. Size-modified PB agrees with replica exchange molecular dynamics much better than nonlinear PB when the ion sizes are chosen from atomistic simulations. The distribution of ions 14 Å away from the RNA central axis are reasonably well reproduced by size-modified PB for all ion types with a uniform solvent dielectric model and a sharp dielectric boundary between solvent and RNA. However, this model does not agree with MD for shorter distances from the A-RNA. A distance-dependent solvent dielectric function proposed by another research group improves the agreement for sodium and strontium ions, even for shorter distances from the A-RNA. However, Mg2+ distributions are still at significant variances for shorter distances. PMID:22385854

Gender and socioeconomic status as determinants of waiting time for inpatient surgery in a system with implicit queue management.

PubMed

Arnesen, Kjell E; Erikssen, Jan; Stavem, Knut

2002-12-01

In a system with implicit queue management, to examine gender and socioeconomic status as determinants of waiting time for inpatient surgery, after adjusting for other potential predictors. A cohort of 452 subjects was examined in outpatient clinics of a general hospital and referred to inpatient surgery. They were followed until scheduled hospital admission (n=396) or until the requested procedure no longer was relevant (n=56). We compared waiting time between groups from referral date until hospital admission, using Kaplan-Meier estimates of waiting times and log rank test. A Cox proportional hazards model was used for assessing the risk ratio (RR) of hospital admission for scheduled surgery. Gender and socioeconomic status could not explain variations in waiting time. However, patients with suspected/verified neoplastic disease or a risk of serious deterioration without treatment had markedly shorter waiting times than the reference groups, with adjusted RR (95% confidence intervals (95%CI)) of time to receiving in-patient surgery of 2.3 (1.7-3.0) and 2.0 (1.3-3.0), respectively. Being on sick leave was associated with shorter waiting time, adjusted RR of 1.7 (1.2-2.5). Referrals from within the hospital or other hospitals had also shorter waiting times than referrals from primary health care physicians, adjusted RR=1.4 (1.1-1.8). There was no evidence of bias against women or people in lower socioeconomic classes in this implicit queue management system. However, patients' access to inpatient surgery was associated with malignancy, prognosis, sick leave status, physician experience, referral pattern and the major diagnosis category.

The risk of shorter fasting time for pediatric deep sedation.

PubMed

Clark, Mathew; Birisci, Esma; Anderson, Jordan E; Anliker, Christina M; Bryant, Micheal A; Downs, Craig; Dalabih, Abdallah

2016-01-01

Current guidelines adopted by the American Academy of Pediatrics calls for prolonged fasting times before performing pediatric procedural sedation and analgesia (PSA). PSA is increasingly provided to children outside of the operating theater by sedation trained pediatric providers and does not require airway manipulation. We investigated the safety of a shorter fasting time compared to a longer and guideline compliant fasting time. We tried to identify the association between fasting time and sedation-related complications. This is a prospective observational study that included children 2 months to 18 years of age and had an American Society of Anesthesiologists physical status classification of I or II, who underwent deep sedation for elective procedures, performed by pediatric critical care providers. Procedures included radiologic imaging studies, electroencephalograms, auditory brainstem response, echocardiograms, Botox injections, and other minor surgical procedures. Subjects were divided into two groups depending on the length of their fasting time (4-6 h and >6 h). Complication rates were calculated and compared between the three groups. In the studied group of 2487 subjects, 1007 (40.5%) had fasting time of 4-6 h and the remaining 1480 (59.5%) subjects had fasted for >6 h. There were no statistically significant differences in any of the studied complications between the two groups. This study found no difference in complication rate in regard to the fasting time among our subjects cohort, which included only healthy children receiving elective procedures performed by sedation trained pediatric critical care providers. This suggests that using shorter fasting time may be safe for procedures performed outside of the operating theater that does not involve high-risk patients or airway manipulation.

[Development and practice evaluation of blood acid-base imbalance analysis software].

PubMed

Chen, Bo; Huang, Haiying; Zhou, Qiang; Peng, Shan; Jia, Hongyu; Ji, Tianxing

2014-11-01

To develop a blood gas, acid-base imbalance analysis computer software to diagnose systematically, rapidly, accurately and automatically determine acid-base imbalance type, and evaluate the clinical application. Using VBA programming language, a computer aided diagnostic software for the judgment of acid-base balance was developed. The clinical data of 220 patients admitted to the Second Affiliated Hospital of Guangzhou Medical University were retrospectively analyzed. The arterial blood gas [pH value, HCO(3)(-), arterial partial pressure of carbon dioxide (PaCO₂)] and electrolytes included data (Na⁺ and Cl⁻) were collected. Data were entered into the software for acid-base imbalances judgment. At the same time the data generation was calculated manually by H-H compensation formula for determining the type of acid-base imbalance. The consistency of judgment results from software and manual calculation was evaluated, and the judgment time of two methods was compared. The clinical diagnosis of the types of acid-base imbalance for the 220 patients: 65 cases were normal, 90 cases with simple type, mixed type in 41 cases, and triplex type in 24 cases. The accuracy of the judgment results of the normal and triplex types from computer software compared with which were calculated manually was 100%, the accuracy of the simple type judgment was 98.9% and 78.0% for the mixed type, and the total accuracy was 95.5%. The Kappa value of judgment result from software and manual judgment was 0.935, P=0.000. It was demonstrated that the consistency was very good. The time for software to determine acid-base imbalances was significantly shorter than the manual judgment (seconds:18.14 ± 3.80 vs. 43.79 ± 23.86, t=7.466, P=0.000), so the method of software was much faster than the manual method. Software judgment can replace manual judgment with the characteristics of rapid, accurate and convenient, can improve work efficiency and quality of clinical doctors and has great clinical application promotion value.

Online Planning Algorithm

NASA Technical Reports Server (NTRS)

Rabideau, Gregg R.; Chien, Steve A.

2010-01-01

AVA v2 software selects goals for execution from a set of goals that oversubscribe shared resources. The term goal refers to a science or engineering request to execute a possibly complex command sequence, such as image targets or ground-station downlinks. Developed as an extension to the Virtual Machine Language (VML) execution system, the software enables onboard and remote goal triggering through the use of an embedded, dynamic goal set that can oversubscribe resources. From the set of conflicting goals, a subset must be chosen that maximizes a given quality metric, which in this case is strict priority selection. A goal can never be pre-empted by a lower priority goal, and high-level goals can be added, removed, or updated at any time, and the "best" goals will be selected for execution. The software addresses the issue of re-planning that must be performed in a short time frame by the embedded system where computational resources are constrained. In particular, the algorithm addresses problems with well-defined goal requests without temporal flexibility that oversubscribes available resources. By using a fast, incremental algorithm, goal selection can be postponed in a "just-in-time" fashion allowing requests to be changed or added at the last minute. Thereby enabling shorter response times and greater autonomy for the system under control.

"Internet of Things" Real-Time Free Flap Monitoring.

PubMed

Kim, Sang Hun; Shin, Ho Seong; Lee, Sang Hwan

2018-01-01

Free flaps are a common treatment option for head and neck reconstruction in plastic reconstructive surgery, and monitoring of the free flap is the most important factor for flap survival. In this study, the authors performed real-time free flap monitoring based on an implanted Doppler system and "internet of things" (IoT)/wireless Wi-Fi, which is a convenient, accurate, and efficient approach for surgeons to monitor a free flap. Implanted Doppler signals were checked continuously until the patient was discharged by the surgeon and residents using their own cellular phone or personal computer. If the surgeon decided that a revision procedure or exploration was required, the authors checked the consumed time (positive signal-to-operating room time) from the first notification when the flap's status was questioned to the determination for revision surgery according to a chart review. To compare the efficacy of real-time monitoring, the authors paired the same number of free flaps performed by the same surgeon and monitored the flaps using conventional methods such as a physical examination. The total survival rate was greater in the real-time monitoring group (94.7% versus 89.5%). The average time for the real-time monitoring group was shorter than that for the conventional group (65 minutes versus 86 minutes). Based on this study, real-time free flap monitoring using IoT technology is a method that surgeon and reconstruction team can monitor simultaneously at any time in any situation.

Diels–Alder Exo-Selectivity in Terminal-Substituted Dienes and Dienophiles: Experimental Discoveries and Computational Explanations

PubMed Central

Lam, Yu-hong; Cheong, Paul Ha-Yeon; Mata, José M. Blasco; Stanway, Steven J.; Gouverneur, Véronique; Houk, K. N.

2009-01-01

The Diels–Alder reactions of a series of silyloxydienes and silylated dienes with acyclic α,β-unsaturated ketones and N-acyloxazolidinones have been investigated. The endo/exo stereochemical outcome is strongly influenced by the substitution pattern of the reactants. High exo selectivity was observed when the termini of the diene and the dienophile involved in the shorter forming bond are both substituted, while the normal endo preference was found otherwise. The exo-selective asymmetric Diels–Alder reactions using Evans’ oxazolidinone chiral auxiliary furnished a high level of π-facial selectivity in the same sense as their well-documented endo-selective counterparts. Computational results of these Diels–Alder reactions were consistent with the experimental endo/exo selectivity in most cases. A twist-asynchronous model accounts for the geometries and energies of the computed transition structures. PMID:19154113

Astrophysical implications of hypothetical stable TeV-scale black holes

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

Giddings, Steven B.; Mangano, Michelangelo L.

2008-08-01

We analyze macroscopic effects of TeV-scale black holes, such as could possibly be produced at the LHC, in what is regarded as an extremely hypothetical scenario in which they are stable and, if trapped inside Earth, begin to accrete matter. We examine a wide variety of TeV-scale gravity scenarios, basing the resulting accretion models on first-principles, basic, and well-tested physical laws. These scenarios fall into two classes, depending on whether accretion could have any macroscopic effect on the Earth at times shorter than the Sun's natural lifetime. We argue that cases with such an effect at shorter times than themore » solar lifetime are ruled out, since in these scenarios black holes produced by cosmic rays impinging on much denser white dwarfs and neutron stars would then catalyze their decay on time scales incompatible with their known lifetimes. We also comment on relevant lifetimes for astronomical objects that capture primordial black holes. In short, this study finds no basis for concerns that TeV-scale black holes from the LHC could pose a risk to Earth on time scales shorter than the Earth's natural lifetime. Indeed, conservative arguments based on detailed calculations and the best-available scientific knowledge, including solid astronomical data, conclude, from multiple perspectives, that there is no risk of any significance whatsoever from such black holes.« less

Ablation of silicon with bursts of femtosecond laser pulses

NASA Astrophysics Data System (ADS)

Gaudiuso, Caterina; Kämmer, Helena; Dreisow, Felix; Ancona, Antonio; Tünnermann, Andreas; Nolte, Stefan

2016-03-01

We report on an experimental investigation of ultrafast laser ablation of silicon with bursts of pulses. The pristine 1030nm-wavelength 200-fs pulses were split into bursts of up to 16 sub-pulses with time separation ranging from 0.5ps to 4080ps. The total ablation threshold fluence was measured depending on the burst features, finding that it strongly increases with the number of sub-pulses for longer sub-pulse delays, while a slowly increasing trend is observed for shorter separation time. The ablation depth per burst follows two different trends according to the time separation between the sub-pulses, as well as the total threshold fluence. For delays shorter than 4ps it decreases with the number of pulses, while for time separations longer than 510ps, deeper craters were achieved by increasing the number of subpulses in the burst, probably due to a change of the effective penetration depth.

[Total laryngectomy using a linear stapler for laryngeal cancer].

PubMed

Tomifuji, Masayuki; Araki, Koji; Kamide, Daisuke; Tanaka, Shingo; Tanaka, Yuya; Fukumori, Takayuki; Shiotani, Akihiro

2014-06-01

Total laryngectomy is a well established method for the treatment of laryngeal cancer. In some cases such as elderly patients or patients with severe complications, a shorter surgical time is preferred. Total laryngectomy using a linear stapler is reportedly advantageous for shortening of the surgical time and for lowering the rate of pharyngeal fistula formation. We applied this surgical technique in three laryngeal cancer cases. After skeletonization of the larynx, the linear stapler is inserted between the larynx and the pharyngeal mucosa. Excision of the larynx and suturing of the pharyngeal mucosa are performed simultaneously. Although the number of cases is small for statistical analysis, the surgical time was shortened by about 30 minutes compared to laryngectomy with manual suturing. Total laryngectomy by linear stapler cannot be applied in all cases of advanced laryngeal cancer. However, if the tumor is confined to the endolarynx, it is a useful tool for some cases that require a shorter surgical time.

Complete Versus Incomplete Angiography Prior to Percutaneous Coronary Intervention in ST-Elevation Myocardial Infarction.

PubMed

Stiver, Kevin; Gao, Xu; Shreenivas, Satya; Boudoulas, Konstantinos Dean; Mazzaferri, Ernie; Makki, Nader; Lilly, Scott M

2017-08-01

Shorter reperfusion times in ST-elevation myocardial infarction (STEMI) are associated with improved survival. Prehospital strategies have been developed to minimize door-to-balloon (DTB) time, but few strategies within the catheterization laboratory itself have been evaluated. Incomplete angiography (IA) prior to percutaneous coronary intervention (PCI) is undertaken in clinical practice as a means to further reduce DTB time. We sought to determine whether or not those with STEMI who underwent IA prior to PCI had different preprocedural characteristics or post-PCI outcomes. We retrospectively reviewed patients presenting to our institution between March 2013 and December 2015. Clinical, demographic, and angiographic data were reviewed. The frequency, predictors, and outcomes among those who received IA vs complete angiography (CA) prior to PCI were compared with analysis of variance. Two hundred fifty-six patients were identified; 68 patients (26.6%) underwent IA and 188 patients (73.4%) had CA prior to PCI. Patients who received IA were younger, but no other preprocedural factors were predictive of IA. The practice of IA did vary by operator (range, 0%-47%; P<.01). DTB times were shorter in the IA group (28.1 min vs 37.3 min; P<.01). Overall outcomes, including peak troponin values, length of stay, in-hospital mortality, and discharge ejection fraction did not differ between the groups. IA is associated with shorter DTB times, although in this population was not associated with improvements in short-term outcomes.

Time-to-treatment of mental disorders in a community sample of Dutch adolescents. A TRAILS study.

PubMed

Raven, D; Jörg, F; Visser, E; Oldehinkel, A J; Schoevers, R A

2017-04-01

Timely recognition and treatment of mental disorders with an onset in childhood and adolescence is paramount, as these are characterized by greater severity and longer persistence than disorders with an onset in adulthood. Studies examining time-to-treatment, also referred to as treatment delay, duration of untreated illness or latency to treatment, and defined as the time between disorder onset and initial treatment contact, are sparse and all based on adult samples. The aim of this study was to describe time-to-treatment and its correlates for any health care professional (any care) and secondary mental health care (secondary care), for a broad range of mental disorders, in adolescents. Data from the Dutch community-based cohort study TRacking Adolescents' Individual Lives Survey (TRAILS; N = 2230) were used. The Composite International Diagnostic Interview (CIDI) was administered to assess DSM-IV disorders, the age of onset, and the age of initial treatment contact with any health care professional in 1584 adolescents of 18-20 years old. In total 43% of the adolescents (n = 675) were diagnosed with a lifetime DSM-IV disorder. The age of initial treatment contact with secondary care was based on administrative records from 321 adolescents without a disorder onset before the age of 10. Descriptive statistics, cumulative lifetime probability plots, and Cox regression analyses were used analyze time-to-treatment. The proportion of adolescents who reported lifetime treatment contact with any care varied from 15% for alcohol dependence to 82% for dysthymia. Regarding secondary care, proportions of lifetime treatment contact were lower for mood disorders and higher for substance dependence. Time-to-treatment for any care varied considerably between and within diagnostic classes. The probability of lifetime treatment contact for mood disorders was above 90%, whereas for other mental disorders this was substantially lower. An earlier age of onset predicted a longer, and the presence of a co-morbid mood disorder predicted a shorter time-to-treatment in general. Disorder severity predicted a shorter time-to-treatment for any care, but not for secondary care. Time-to-treatment for secondary care was shorter for adolescents from low and middle socioeconomic background than for adolescents from a high socioeconomic background. Although the time-to-treatment was shorter for adolescents than for adults, it was still substantial, and the overall patterns were remarkably similar to those found in adults. Efforts to reduce time-to-treatment should therefore be aimed at children and adolescents. Future research should address mechanisms underlying time-to-treatment and its consequences for early-onset disorders in particular.

Time to Detection with BacT/Alert FA Plus Compared to BacT/Alert FA Blood Culture Media.

PubMed

Nutman, A; Fisher Even-Tsur, S; Shapiro, G; Braun, T; Schwartz, D; Carmeli, Y

2016-09-01

Rapid identification of the causative pathogen in patients with bacteremia allows adjustment of antibiotic therapy and improves patient outcomes. We compared in vitro and real-life time to detection (TTD) of two blood culture media, BacT/Alert FA (FA) and BacT/Alert FA Plus (FA Plus), for the nine most common species of bacterial pathogens recovered from blood samples. Experimental data from simulated cultures was compared with microbiology records of TTD for both culture media with growth of the species of interest in clinical blood cultures. In the experimental conditions, median TTD was 3.8 hours (23.9 %) shorter using FA Plus media. The magnitude of reduction differed between species. Similarly, in real life data, FA Plus had shorter TTD than FA media; however, the difference between culture media was smaller, and median TTD was only 1 hour (8.5 %) less. We found shorter TTD with BacT/Alert FA Plus culture media, both experimentally and in real-life conditions and unrelated to antibiotic neutralization, highlighting the importance of appropriate blood culture media selection.

Noninvasive blood pressure measurement scheme based on optical fiber sensor

NASA Astrophysics Data System (ADS)

Liu, Xianxuan; Yuan, Xueguang; Zhang, Yangan

2016-10-01

Optical fiber sensing has many advantages, such as volume small, light quality, low loss, strong in anti-jamming. Since the invention of the optical fiber sensing technology in 1977, optical fiber sensing technology has been applied in the military, national defense, aerospace, industrial, medical and other fields in recent years, and made a great contribution to parameter measurement in the environment under the limited condition .With the rapid development of computer, network system, the intelligent optical fiber sensing technology, the sensor technology, the combination of computer and communication technology , the detection, diagnosis and analysis can be automatically and efficiently completed. In this work, we proposed a noninvasive blood pressure detection and analysis scheme which uses optical fiber sensor. Optical fiber sensing system mainly includes the light source, optical fiber, optical detector, optical modulator, the signal processing module and so on. wavelength optical signals were led into the optical fiber sensor and the signals reflected by the human body surface were detected. By comparing actual testing data with the data got by traditional way to measure the blood pressure we can establish models for predicting the blood pressure and achieve noninvasive blood pressure measurement by using spectrum analysis technology. Blood pressure measurement method based on optical fiber sensing system is faster and more convenient than traditional way, and it can get accurate analysis results in a shorter period of time than before, so it can efficiently reduce the time cost and manpower cost.

Clinical and Procedural Predictors of Outcomes From the Endovascular Treatment of Posterior Circulation Strokes.

PubMed

Mokin, Maxim; Sonig, Ashish; Sivakanthan, Sananthan; Ren, Zeguang; Elijovich, Lucas; Arthur, Adam; Goyal, Nitin; Kan, Peter; Duckworth, Edward; Veznedaroglu, Erol; Binning, Mandy J; Liebman, Kenneth M; Rao, Vikas; Turner, Raymond D; Turk, Aquilla S; Baxter, Blaise W; Dabus, Guilherme; Linfante, Italo; Snyder, Kenneth V; Levy, Elad I; Siddiqui, Adnan H

2016-03-01

Patients with posterior circulation strokes have been excluded from recent randomized endovascular stroke trials. We reviewed the recent multicenter experience with endovascular treatment of posterior circulation strokes to identify the clinical, radiographic, and procedural predictors of successful recanalization and good neurological outcomes. We performed a multicenter retrospective analysis of consecutive patients with posterior circulation strokes, who underwent thrombectomy with stent retrievers or primary aspiration thrombectomy (including A Direct Aspiration First Pass Technique [ADAPT] approach). We correlated clinical and radiographic outcomes with demographic, clinical, and technical characteristics. A total of 100 patients were included in the final analysis (mean age, 63.5±14.2 years; mean admission National Institutes of Health Stroke Scale score, 19.2±8.2). Favorable clinical outcome at 3 months (modified Rankin Scale score ≤2) was achieved in 35% of patients. Successful recanalization and shorter time from stroke onset to the start of the procedure were significant predictors of favorable clinical outcome at 90 days. Stent retriever and aspiration thrombectomy as primary treatment approaches showed comparable procedural and clinical outcomes. None of the baseline advanced imaging modalities (magnetic resonance imaging, computed tomographic perfusion, or computed tomography angiography assessment of collaterals) showed superiority in selecting patients for thrombectomy. Time to the start of the procedure is an important predictor of clinical success after thrombectomy in patients with posterior circulation strokes. Both stent retriever and aspiration thrombectomy as primary treatment approaches are effective in achieving successful recanalization. © 2016 American Heart Association, Inc.

Effect of environmental factors on the kinetics of insulin fibril formation: elucidation of the molecular mechanism.

PubMed

Nielsen, L; Khurana, R; Coats, A; Frokjaer, S; Brange, J; Vyas, S; Uversky, V N; Fink, A L

2001-05-22

In the search for the molecular mechanism of insulin fibrillation, the kinetics of insulin fibril formation were studied under different conditions using the fluorescent dye thioflavin T (ThT). The effect of insulin concentration, agitation, pH, ionic strength, anions, seeding, and addition of 1-anilinonaphthalene-8-sulfonic acid (ANS), urea, TMAO, sucrose, and ThT on the kinetics of fibrillation was investigated. The kinetics of the fibrillation process could be described by the lag time for formation of stable nuclei (nucleation) and the apparent rate constant for the growth of fibrils (elongation). The addition of seeds eliminated the lag phase. An increase in insulin concentration resulted in shorter lag times and faster growth of fibrils. Shorter lag times and faster growth of fibrils were seen at acidic pH versus neutral pH, whereas an increase in ionic strength resulted in shorter lag times and slower growth of fibrils. There was no clear correlation between the rate of fibril elongation and ionic strength. Agitation during fibril formation attenuated the effects of insulin concentration and ionic strength on both lag times and fibril growth. The addition of ANS increased the lag time and decreased the apparent growth rate for insulin fibril formation. The ANS-induced inhibition appears to reflect the formation of amorphous aggregates. The denaturant, urea, decreased the lag time, whereas the stabilizers, trimethylamine N-oxide dihydrate (TMAO) and sucrose, increased the lag times. The results indicated that both nucleation and fibril growth were controlled by hydrophobic and electrostatic interactions. A kinetic model, involving the association of monomeric partially folded intermediates, whose concentration is stimulated by the air-water interface, leading to formation of the critical nucleus and thence fibrils, is proposed.

Gas Chromatograph Method Optimization Trade Study for RESOLVE: 20-meter Column v. 8-meter Column

NASA Technical Reports Server (NTRS)

Huz, Kateryna

2014-01-01

RESOLVE is the payload on a Class D mission, Resource Prospector, which will prospect for water and other volatile resources at a lunar pole. The RESOLVE payload's primary scientific purpose includes determining the presence of water on the moon in the lunar regolith. In order to detect the water, a gas chromatograph (GC) will be used in conjunction with a mass spectrometer (MS). The goal of the experiment was to compare two GC column lengths and recommend which would be best for RESOLVE's purposes. Throughout the experiment, an Inficon Fusion GC and an Inficon Micro GC 3000 were used. The Fusion had a 20m long column with 0.25mm internal diameter (Id). The Micro GC 3000 had an 8m long column with a 0.32mm Id. By varying the column temperature and column pressure while holding all other parameters constant, the ideal conditions for testing with each column length in their individual instrument configurations were determined. The criteria used for determining the optimal method parameters included (in no particular order) (1) quickest run time, (2) peak sharpness, and (3) peak separation. After testing numerous combinations of temperature and pressure, the parameters for each column length that resulted in the most optimal data given my three criteria were selected. The ideal temperature and pressure for the 20m column were 95 C and 50psig. At this temperature and pressure, the peaks were separated and the retention times were shorter compared to other combinations. The Inficon Micro GC 3000 operated better at lower temperature mainly due to the shorter 8m column. The optimal column temperature and pressure were 70 C and 30psig. The Inficon Micro GC 3000 8m column had worse separation than the Inficon Fusion 20m column, but was able to separate water within a shorter run time. Therefore, the most significant tradeoff between the two column lengths was peak separation of the sample versus run time. After performing several tests, it was concluded that better detection via good peak separation with a longer run time is a better asset than moderate peak separation with a shorter run time. Even given that RESOLVE is highly interested in water and that mission timeline is of significant importance given the short seven-to-ten-day mission timeline, worse detection with an 8m column may lead to overlooking other substances existing on the moon that could advance planetary science. Thus, I recommend the 20m column. However, if mission timeline and water separation are deemed the highest priority, the 8m column should be selected due to its ability to separate water within a shorter run time than the 20m column.

The ergonomics of laparoscopic surgery: a quantitative study of the time and motion of laparoscopic surgeons in live surgical environments.

PubMed

Aitchison, Lucy Ping; Cui, Cathy Kexin; Arnold, Amy; Nesbitt-Hawes, Erin; Abbott, Jason

2016-11-01

Laparoscopic surgery presents multiple ergonomic difficulties for the surgeon, requiring awkward body postures and prolonged static muscle loading that increases risk of musculoskeletal strain and injury. This prospective study quantitatively measures the biomechanical movements of surgeons during laparoscopic procedures to determine at-risk movements from prolonged static muscle loading and repetitive motions that may lead to injury. A total of 150 video recordings of 18 surgeons, standing at the patient's left, were captured from three fixed camera positions during live gynecological laparoscopic surgery. Postoperative processing quantified surgeon movements at the neck, shoulders and elbows using computer software to measure extreme joint angles and time spent within defined joint angle ranges. Surgeons spent a median of 98 % (range 77-100 %) of surgical time with their neck rotated at 21° (range 0°-52°). The non-dominant arm was subjected to more extreme positions for significantly longer periods of time compared to the dominant, with shoulder flexion at 45°-90° for 35 vs. 0 % (p < 0.001) and elbow flexion at >120° for 31 vs. 0 % (p < 0.001) of total surgical time. Procedures involving power morcellation required significantly greater number of instrument insertion/removals-119 (range 56-182) compared with 12 (range 2-122) when morcellation was not used (p < 0.001). Shorter surgeons maintained significantly greater degrees of neck rotation when viewing the monitor (p < 0.003) and surgeons with shorter arm lengths spent longer in extreme positions with their non-dominant shoulder at >90° (p = 0.04) and elbow at >120° (p < 0.001) compared with taller surgeons. No significant correlations were found between BMI or surgical experience and more extreme joint positions. Four primary areas have been identified where surgeons are consistently demonstrating movements that increase their risk of harm: (1) extended periods of neck rotation; (2) asymmetrical loading between the dominant and non-dominant shoulders; (3) power morcellation and frequent insertions/removals of laparoscopic instruments resulting in repetitions of the most extreme shoulder positions and (4) a negative correlation between height and percentage time spent in more extreme positions.

Dynamics of Bottlebrush Networks

NASA Astrophysics Data System (ADS)

Cao, Zhen; Daniel, William; Vatankhah-Varnosfaderani, Mohammad; Sheiko, Sergei; Dobrynin, Andrey

The deformation dynamics of bottlebrush networks in a melt state is studied using a combination of theoretical, computational, and experimental techniques. Three main molecular relaxation processes are identified in these systems: (i) relaxation of the side chains, (ii) relaxation of the bottlebrush backbones on length scales shorter than the bottlebrush Kuhn length (bK) , and (iii) relaxation of the bottlebrush network strands between cross-links. The relaxation of side chains having a degree of polymerization (DP), nsc, dominates the network dynamics on the time scales τ0 < t <=τsc , where τ0 and τsc τ0 (nsc + 1)2 are the characteristic relaxation times of monomeric units and side chains, respectively. In this time interval, the shear modulus at small deformations decays with time as G0BB (t) t - 1 / 2. On time scales t >τsc, bottlebrush elastomers behave as networks of filaments with a shear modulus G0BB (t) (nsc + 1)- 1 / 4t - 1 / 2 . Finally, the response of the bottlebrush networks becomes time independent at times scales longer than the Rouse time of the bottlebrush network strands. In this time interval, the network shear modulus depends on the network molecular parameters as G0BB (t) (nsc + 1)-1N-1 . Analysis of the simulation data shows that the stress evolution in the bottlebrush networks during constant strain-rate deformation can be described by a universal function. NSF DMR-1409710, DMR-1407645, DMR-1624569, DMR-1436201.

Effects of shortened host life span on the evolution of parasite life history and virulence in a microbial host-parasite system

PubMed Central

Nidelet, Thibault; Koella, Jacob C; Kaltz, Oliver

2009-01-01

Background Ecological factors play an important role in the evolution of parasite exploitation strategies. A common prediction is that, as shorter host life span reduces future opportunities of transmission, parasites compensate with an evolutionary shift towards earlier transmission. They may grow more rapidly within the host, have a shorter latency time and, consequently, be more virulent. Thus, increased extrinsic (i.e., not caused by the parasite) host mortality leads to the evolution of more virulent parasites. To test these predictions, we performed a serial transfer experiment, using the protozoan Paramecium caudatum and its bacterial parasite Holospora undulata. We simulated variation in host life span by killing hosts after 11 (early killing) or 14 (late killing) days post inoculation; after killing, parasite transmission stages were collected and used for a new infection cycle. Results After 13 cycles (≈ 300 generations), parasites from the early-killing treatment were less infectious, but had shorter latency time and higher virulence than those from the late-killing treatment. Overall, shorter latency time was associated with higher parasite loads and thus presumably with more rapid within-host replication. Conclusion The analysis of the means of the two treatments is thus consistent with theory, and suggests that evolution is constrained by trade-offs between virulence, transmission and within-host growth. In contrast, we found little evidence for such trade-offs across parasite selection lines within treatments; thus, to some extent, these traits may evolve independently. This study illustrates how environmental variation (experienced by the host) can lead to the evolution of distinct parasite strategies. PMID:19320981

A real-world, multi-site, observational study of infusion time and treatment satisfaction with rheumatoid arthritis patients treated with intravenous golimumab or infliximab.

PubMed

Daniel, Shoshana R; McDermott, John D; Le, Cathy; Pierce, Christine A; Ziskind, Michael A; Ellis, Lorie A

2018-05-25

To assess real-world infusion times for golimumab (GLM-IV) and infliximab (IFX) for rheumatoid arthritis (RA) patients and factors associated with treatment satisfaction. An observational study assessed infusion time including: clinic visit duration, RA medication preparation and infusion time, and infusion process time. Satisfaction was assessed by a modified Treatment Satisfaction Questionnaire for Medication (patient) and study-specific questionnaires (patient and clinic personnel). Comparative statistical testing for patient data utilized analysis of variance for continuous measures, and Fisher's exact or Chi-square test for categorical measures. Multivariate analysis was performed for the primary time endpoints and patient satisfaction. One hundred and fifty patients were enrolled from six US sites (72 GLM-IV, 78 IFX). The majority of patients were female (80.0%) and Caucasian (88.7%). GLM-IV required fewer vials per infusion (3.7) compared to IFX (4.9; p = .0001). Clinic visit duration (minutes) was shorter for GLM-IV (65.1) compared to IFX (153.1; p < .0001), as was total infusion time for RA medication (32.8 GLM-IV, 119.5 IFX; p < .0001) and infusion process times (45.8 GLM-IV, 134.1 IFX; p < .0001). Patients treated with GLM-IV reported higher satisfaction ratings with infusion time (p < .0001) and total visit time (p = .0003). Clinic personnel reported higher satisfaction with GLM-IV than IFX specific to medication preparation time, ease of mixing RA medication, frequency of patients requiring pre-medication, and infusion time. Findings may not be representative of care delivery for all RA infusion practices or RA patients. Shorter overall clinic visit duration, infusion process, and RA medication infusion times were observed for GLM-IV compared to IFX. A shorter duration in infusion time was associated with higher patient and clinic personnel satisfaction ratings.

Fundamental Insights into Proton-Coupled Electron Transfer in Soybean Lipoxygenase from Quantum Mechanical/Molecular Mechanical Free Energy Simulations.

PubMed

Li, Pengfei; Soudackov, Alexander V; Hammes-Schiffer, Sharon

2018-02-28

The proton-coupled electron transfer (PCET) reaction catalyzed by soybean lipoxygenase has served as a prototype for understanding hydrogen tunneling in enzymes. Herein this PCET reaction is studied with mixed quantum mechanical/molecular mechanical (QM/MM) free energy simulations. The free energy surfaces are computed as functions of the proton donor-acceptor (C-O) distance and the proton coordinate, and the potential of mean force is computed as a function of the C-O distance, inherently including anharmonicity. The simulation results are used to calculate the kinetic isotope effects for the wild-type enzyme (WT) and the L546A/L754A double mutant (DM), which have been measured experimentally to be ∼80 and ∼700, respectively. The PCET reaction is found to be exoergic for WT and slightly endoergic for the DM, and the equilibrium C-O distance for the reactant is found to be ∼0.2 Å greater for the DM than for WT. The larger equilibrium distance for the DM, which is due mainly to less optimal substrate binding in the expanded binding cavity, is primarily responsible for its higher kinetic isotope effect. The calculated potentials of mean force are anharmonic and relatively soft at shorter C-O distances, allowing efficient thermal sampling of the shorter distances required for effective hydrogen tunneling. The primarily local electrostatic field at the transferring hydrogen is ∼100 MV/cm in the direction to facilitate proton transfer and increases dramatically as the C-O distance decreases. These simulations suggest that the overall protein environment is important for conformational sampling of active substrate configurations aligned for proton transfer, but the PCET reaction is influenced primarily by local electrostatic effects that facilitate conformational sampling of shorter proton donor-acceptor distances required for effective hydrogen tunneling.

Estimation of Spatiotemporal Sensitivity Using Band-limited Signals with No Additional Acquisitions for k-t Parallel Imaging.

PubMed

Takeshima, Hidenori; Saitoh, Kanako; Nitta, Shuhei; Shiodera, Taichiro; Takeguchi, Tomoyuki; Bannae, Shuhei; Kuhara, Shigehide

2018-03-13

Dynamic MR techniques, such as cardiac cine imaging, benefit from shorter acquisition times. The goal of the present study was to develop a method that achieves short acquisition times, while maintaining a cost-effective reconstruction, for dynamic MRI. k - t sensitivity encoding (SENSE) was identified as the base method to be enhanced meeting these two requirements. The proposed method achieves a reduction in acquisition time by estimating the spatiotemporal (x - f) sensitivity without requiring the acquisition of the alias-free signals, typical of the k - t SENSE technique. The cost-effective reconstruction, in turn, is achieved by a computationally efficient estimation of the x - f sensitivity from the band-limited signals of the aliased inputs. Such band-limited signals are suitable for sensitivity estimation because the strongly aliased signals have been removed. For the same reduction factor 4, the net reduction factor 4 for the proposed method was significantly higher than the factor 2.29 achieved by k - t SENSE. The processing time is reduced from 4.1 s for k - t SENSE to 1.7 s for the proposed method. The image quality obtained using the proposed method proved to be superior (mean squared error [MSE] ± standard deviation [SD] = 6.85 ± 2.73) compared to the k - t SENSE case (MSE ± SD = 12.73 ± 3.60) for the vertical long-axis (VLA) view, as well as other views. In the present study, k - t SENSE was identified as a suitable base method to be improved achieving both short acquisition times and a cost-effective reconstruction. To enhance these characteristics of base method, a novel implementation is proposed, estimating the x - f sensitivity without the need for an explicit scan of the reference signals. Experimental results showed that the acquisition, computational times and image quality for the proposed method were improved compared to the standard k - t SENSE method.

Improved workflow for quantification of left ventricular volumes and mass using free-breathing motion corrected cine imaging.

PubMed

Cross, Russell; Olivieri, Laura; O'Brien, Kendall; Kellman, Peter; Xue, Hui; Hansen, Michael

2016-02-25

Traditional cine imaging for cardiac functional assessment requires breath-holding, which can be problematic in some situations. Free-breathing techniques have relied on multiple averages or real-time imaging, producing images that can be spatially and/or temporally blurred. To overcome this, methods have been developed to acquire real-time images over multiple cardiac cycles, which are subsequently motion corrected and reformatted to yield a single image series displaying one cardiac cycle with high temporal and spatial resolution. Application of these algorithms has required significant additional reconstruction time. The use of distributed computing was recently proposed as a way to improve clinical workflow with such algorithms. In this study, we have deployed a distributed computing version of motion corrected re-binning reconstruction for free-breathing evaluation of cardiac function. Twenty five patients and 25 volunteers underwent cardiovascular magnetic resonance (CMR) for evaluation of left ventricular end-systolic volume (ESV), end-diastolic volume (EDV), and end-diastolic mass. Measurements using motion corrected re-binning were compared to those using breath-held SSFP and to free-breathing SSFP with multiple averages, and were performed by two independent observers. Pearson correlation coefficients and Bland-Altman plots tested agreement across techniques. Concordance correlation coefficient and Bland-Altman analysis tested inter-observer variability. Total scan plus reconstruction times were tested for significant differences using paired t-test. Measured volumes and mass obtained by motion corrected re-binning and by averaged free-breathing SSFP compared favorably to those obtained by breath-held SSFP (r = 0.9863/0.9813 for EDV, 0.9550/0.9685 for ESV, 0.9952/0.9771 for mass). Inter-observer variability was good with concordance correlation coefficients between observers across all acquisition types suggesting substantial agreement. Both motion corrected re-binning and averaged free-breathing SSFP acquisition and reconstruction times were shorter than breath-held SSFP techniques (p < 0.0001). On average, motion corrected re-binning required 3 min less than breath-held SSFP imaging, a 37% reduction in acquisition and reconstruction time. The motion corrected re-binning image reconstruction technique provides robust cardiac imaging that can be used for quantification that compares favorably to breath-held SSFP as well as multiple average free-breathing SSFP, but can be obtained in a fraction of the time when using cloud-based distributed computing reconstruction.

Time profile of type 3 bursts in decameter and hectometer range

NASA Technical Reports Server (NTRS)

Takakura, T.; Naito, Y.; Ohki, K.

1973-01-01

The following new hypothesis is proposed. The decay time of plasma waves is much shorter than the time scale of type 3 bursts especially at low frequencies. Accordingly, the time variation of radio flux at a given frequency merely corresponds to the flux of fast electrons passing through the corresponding plasma layer.

Early declaration of death by neurologic criteria results in greater organ donor potential.

PubMed

Resnick, Shelby; Seamon, Mark J; Holena, Daniel; Pascual, Jose; Reilly, Patrick M; Martin, Niels D

2017-10-01

Aggressive management of patients prior to and after determination of death by neurologic criteria (DNC) is necessary to optimize organ recovery, transplantation, and increase the number of organs transplanted per donor (OTPD). The effects of time management are understudied but potentially pivotal component. The objective of this study was to analyze specific time points (time to DNC, time to procurement) and the time intervals between them to better characterize the optimal timeline of organ donation. Using data over a 5-year time period (2011-2015) from the largest US OPO, all patients with catastrophic brain injury and donated transplantable organs were retrospectively reviewed. Active smokers were excluded. Maximum donor potential was seven organs (heart, lungs [2], kidneys [2], liver, and pancreas). Time from admission to declaration of DNC and donation was calculated. Mean time points stratified by specific organ procurement rates and overall OTPD were compared using unpaired t-test. Of 1719 Declaration of Death by Neurologic Criteria organ donors, 381 were secondary to head trauma. Smokers and organs recovered but not transplanted were excluded leaving 297 patients. Males comprised 78.8%, the mean age was 36.0 (±16.8) years, and 87.6% were treated at a trauma center. Higher donor potential (>4 OTPD) was associated with shorter average times from admission to brain death; 66.6 versus 82.2 hours, P = 0.04. Lung donors were also associated with shorter average times from admission to brain death; 61.6 versus 83.6 hours, P = 0.004. The time interval from DNC to donation varied minimally among groups and did not affect donation rates. A shorter time interval between admission and declaration of DNC was associated with increased OTPD, especially lungs. Further research to identify what role timing plays in the management of the potential organ donor and how that relates to donor management goals is needed. Copyright © 2017 Elsevier Inc. All rights reserved.

Efficacy and safety of cryoballoon ablation versus radiofrequency catheter ablation in atrial fibrillation: an updated meta-analysis

PubMed Central

Ma, Honglan; Sun, Dongdong; Luan, Hui; Feng, Wei; Zhou, Yaqiong; Wu, Jine; He, Caiyun

2017-01-01

Introduction Cryoballoon ablation (CBA) and irrigated radiofrequency catheter ablation (RFCA) are the main treatments for drug-refractory symptomatic atrial fibrillation (AF). Aim To compare the efficacy and safety between CBA and RFCA for the treatment of AF. Material and methods We searched the Embase and Medline databases for clinical studies published up to December 2016. Studies that satisfied our predefined inclusion criteria were included. Results After searching through the literature in the two major databases, 20 studies with a total of 9,141 patients were included in our study. The CBA had a significantly shorter procedure time (weighted mean difference (WMD) –30.38 min; 95% CI: –46.43 to –14.33, p = 0.0002) and non-significantly shorter fluoroscopy time (WMD –3.18 min; 95% CI: –6.43 to 0.07, p = 0.06) compared with RFCA. There was no difference in freedom from AF between CBA and RFCA (CBA 78.55% vs. RFCA 83.13%, OR = 1.15, 95% CI: 0.95–1.39, p = 0.14). The CBA was associated with a high risk of procedure-related complications (CBA 9.02% vs. RFCA 6.56%, OR = 1.56, 95% CI: 1.05–2.31, p = 0.03), especially phrenic nerve paralysis (PNP, OR = 10.72, 95% CI: 5.59–20.55, p < 0.00001). The risk of pericardial effusions/cardiac tamponade was low in the CBA group (CBA 1.05% vs. RFCA 1.86%, OR = 0.62, 95% CI: 0.41–0.93, p = 0.02). Conclusions For AF, CBA was as effective as RFCA. However, CBA had a shorter procedure time and a non-significantly shorter fluoroscopy time, a significantly high risk of PNP and a low incidence of pericardial effusions/cardiac tamponade compared with RFCA. PMID:29056997

Sleep Characteristics and Carotid Atherosclerosis Among Midlife Women.

PubMed

Thurston, Rebecca C; Chang, Yuefang; von Känel, Roland; Barinas-Mitchell, Emma; Jennings, J Richard; Hall, Martica H; Santoro, Nanette; Buysse, Daniel J; Matthews, Karen A

2017-02-01

Midlife, which encompasses the menopause transition in women, can be a time of disrupted sleep and accelerated atherosclerosis accumulation. Short or poor sleep quality has been associated with cardiovascular disease (CVD) risk; few studies have investigated relations among midlife women. We tested whether shorter actigraphy sleep time or poorer subjective sleep quality was associated with carotid atherosclerosis among midlife women. Two hundred fifty-six peri- and postmenopausal women aged 40-60 years completed 3 days of wrist actigraphy, hot flash monitoring, questionnaires (Pittsburgh Sleep Quality Index [PSQI], Berlin), a blood draw, and carotid ultrasound [intima media thickness (IMT), plaque]. Associations of objective (actigraphy) and subjective (PSQI) sleep with IMT/plaque were tested in regression models (covariates: age, race, education, body mass index, blood pressure, lipids, insulin resistance, medications, snoring, depressive symptoms, sleep hot flashes, and estradiol). Shorter objective sleep time was associated with higher odds of carotid plaque (for each hour shorter sleep, plaque score ≥ 2, odds ratio (OR) [95% confidence interval, CI] = 1.58 [1.11-2.27], p = .01; plaque score = 1, OR [95% CI] = 0.95 [0.68-1.32], p = .75, vs. no plaque, multivariable). Poorer subjective sleep quality was associated with higher mean IMT [β, b (standard error, SE) = 0.004 (0.002), p = .03], maximal IMT [b (SE) = 0.009 (0.003), p = .005], and plaque [plaque score ≥ 2, OR (95% CI) = 1.23 (1.09-1.40), p = .001; score = 1, OR (95% CI) = 1.06 (0.93-1.21), p = .37, vs. no plaque] in multivariable models. Findings persisted additionally adjusting for sleep hot flashes and estradiol. Shorter actigraphy-assessed sleep time and poorer subjective sleep quality were associated with increased carotid atherosclerosis among midlife women. Associations persisted adjusting for CVD risk factors, hot flashes, and estradiol. © Sleep Research Society 2016. Published by Oxford University Press on behalf of the Sleep Research Society. All rights reserved. For permissions, please e-mail journals.permissions@oup.com.

Multicenter Clinical Evaluation of BacT/Alert Virtuo Blood Culture System.

PubMed

Jacobs, Michael R; Mazzulli, Tony; Hazen, Kevin C; Good, Caryn E; Abdelhamed, Ayman M; Lo, Pauline; Shum, Bianche; Roman, Katharine P; Robinson, Danielle C

2017-08-01

BacT/Alert Virtuo is an advanced, automated blood culture system incorporating improved automation and an enhanced detection algorithm to shorten time to detection. A multicenter study of the investigational Virtuo system (bioMérieux, Inc., Durham, NC) compared to BacT/Alert 3D (BTA3D) for detection of bacteremia/fungemia in four bottle types, SA and FA Plus (aerobic) and SN and FN Plus (anaerobic), was performed in a clinical setting with patient samples in a matched system design clinical trial. Blood was added to paired aerobic or anaerobic bottles, with the volume in each bottle in each pair required to be ≤10 ml and with the volumes required to be within 30% of each other. Of 5,709 bottle sets (52.5% aerobic pairs and 47.5% anaerobic pairs), 430 (7.5%) were positive for bacterial or fungal growth, with 342 (6.0%) clinically significant and 83 (1.5%) contaminated. A total of 3,539 sets (62.0%) were volume compliant, with 203 sets (5.7%) clinically significant. The positivity rates for volume-compliant bottle pairs determined by the two systems were comparable, with 68.7% of clinically significant isolates detected by both instruments, 15.7% by Virtuo only, and 15.7% by BTA3D only. Virtuo detected microbial growth nearly 2 h sooner overall than BTA3D (mean, 15.9 h versus 17.7 h). Shorter time to detection by Virtuo was related to organism group, with the time to detection being significantly shorter for enteric Gram-negative bacilli and enterococci (means, 3.6 h and 2.3 h shorter, respectively). This large clinical study demonstrated that the Virtuo blood culture system produced results comparable to those seen with the long-established BTA3D system, with significantly shorter time to detection. Copyright © 2017 Jacobs et al.

Workload assessment of surgeons: correlation between NASA TLX and blinks.

PubMed

Zheng, Bin; Jiang, Xianta; Tien, Geoffrey; Meneghetti, Adam; Panton, O Neely M; Atkins, M Stella

2012-10-01

Blinks are known as an indicator of visual attention and mental stress. In this study, surgeons' mental workload was evaluated utilizing a paper assessment instrument (National Aeronautics and Space Administration Task Load Index, NASA TLX) and by examining their eye blinks. Correlation between these two assessments was reported. Surgeons' eye motions were video-recorded using a head-mounted eye-tracker while the surgeons performed a laparoscopic procedure on a virtual reality trainer. Blink frequency and duration were computed using computer vision technology. The level of workload experienced during the procedure was reported by surgeons using the NASA TLX. A total of 42 valid videos were recorded from 23 surgeons. After blinks were computed, videos were divided into two groups based on the blink frequency: infrequent group (≤ 6 blinks/min) and frequent group (more than 6 blinks/min). Surgical performance (measured by task time and trajectories of tool tips) was not significantly different between these two groups, but NASA TLX scores were significantly different. Surgeons who blinked infrequently reported a higher level of frustration (46 vs. 34, P = 0.047) and higher overall level of workload (57 vs. 47, P = 0.045) than those who blinked more frequently. The correlation coefficients (Pearson test) between NASA TLX and the blink frequency and duration were -0.17 and 0.446. Reduction of blink frequency and shorter blink duration matched the increasing level of mental workload reported by surgeons. The value of using eye-tracking technology for assessment of surgeon mental workload was shown.

Exploring the quantum speed limit with computer games

NASA Astrophysics Data System (ADS)

Sørensen, Jens Jakob W. H.; Pedersen, Mads Kock; Munch, Michael; Haikka, Pinja; Jensen, Jesper Halkjær; Planke, Tilo; Andreasen, Morten Ginnerup; Gajdacz, Miroslav; Mølmer, Klaus; Lieberoth, Andreas; Sherson, Jacob F.

2016-04-01

Humans routinely solve problems of immense computational complexity by intuitively forming simple, low-dimensional heuristic strategies. Citizen science (or crowd sourcing) is a way of exploiting this ability by presenting scientific research problems to non-experts. ‘Gamification’—the application of game elements in a non-game context—is an effective tool with which to enable citizen scientists to provide solutions to research problems. The citizen science games Foldit, EteRNA and EyeWire have been used successfully to study protein and RNA folding and neuron mapping, but so far gamification has not been applied to problems in quantum physics. Here we report on Quantum Moves, an online platform gamifying optimization problems in quantum physics. We show that human players are able to find solutions to difficult problems associated with the task of quantum computing. Players succeed where purely numerical optimization fails, and analyses of their solutions provide insights into the problem of optimization of a more profound and general nature. Using player strategies, we have thus developed a few-parameter heuristic optimization method that efficiently outperforms the most prominent established numerical methods. The numerical complexity associated with time-optimal solutions increases for shorter process durations. To understand this better, we produced a low-dimensional rendering of the optimization landscape. This rendering reveals why traditional optimization methods fail near the quantum speed limit (that is, the shortest process duration with perfect fidelity). Combined analyses of optimization landscapes and heuristic solution strategies may benefit wider classes of optimization problems in quantum physics and beyond.

Exploring the quantum speed limit with computer games.

PubMed

Sørensen, Jens Jakob W H; Pedersen, Mads Kock; Munch, Michael; Haikka, Pinja; Jensen, Jesper Halkjær; Planke, Tilo; Andreasen, Morten Ginnerup; Gajdacz, Miroslav; Mølmer, Klaus; Lieberoth, Andreas; Sherson, Jacob F

2016-04-14

Humans routinely solve problems of immense computational complexity by intuitively forming simple, low-dimensional heuristic strategies. Citizen science (or crowd sourcing) is a way of exploiting this ability by presenting scientific research problems to non-experts. 'Gamification'--the application of game elements in a non-game context--is an effective tool with which to enable citizen scientists to provide solutions to research problems. The citizen science games Foldit, EteRNA and EyeWire have been used successfully to study protein and RNA folding and neuron mapping, but so far gamification has not been applied to problems in quantum physics. Here we report on Quantum Moves, an online platform gamifying optimization problems in quantum physics. We show that human players are able to find solutions to difficult problems associated with the task of quantum computing. Players succeed where purely numerical optimization fails, and analyses of their solutions provide insights into the problem of optimization of a more profound and general nature. Using player strategies, we have thus developed a few-parameter heuristic optimization method that efficiently outperforms the most prominent established numerical methods. The numerical complexity associated with time-optimal solutions increases for shorter process durations. To understand this better, we produced a low-dimensional rendering of the optimization landscape. This rendering reveals why traditional optimization methods fail near the quantum speed limit (that is, the shortest process duration with perfect fidelity). Combined analyses of optimization landscapes and heuristic solution strategies may benefit wider classes of optimization problems in quantum physics and beyond.

Formation of Minor Phases in a Nickel-Based Disk Superalloy

NASA Technical Reports Server (NTRS)

Gabb, T. P.; Garg, A.; Miller, D. R.; Sudbrack, C. K.; Hull, D. R.; Johnson, D.; Rogers, R. B.; Gayda, J.; Semiatin, S. L.

2012-01-01

The minor phases of powder metallurgy disk superalloy LSHR were studied. Samples were consistently heat treated at three different temperatures for long times to approximate equilibrium. Additional heat treatments were also performed for shorter times, to then assess non-equilibrium conditions. Minor phases including MC carbides, M23C6 carbides, M3B2 borides, and sigma were identified. Their transformation temperatures, lattice parameters, compositions, average sizes and total area fractions were determined, and compared to estimates of an existing phase prediction software package. Parameters measured at equilibrium sometimes agreed reasonably well with software model estimates, with potential for further improvements. Results for shorter times representing non-equilibrium indicated significant potential for further extension of the software to such conditions, which are more commonly observed during heat treatments and service at high temperatures for disk applications.

Effects of Extrinsic Mortality on the Evolution of Aging: A Stochastic Modeling Approach

PubMed Central

Shokhirev, Maxim Nikolaievich; Johnson, Adiv Adam

2014-01-01

The evolutionary theories of aging are useful for gaining insights into the complex mechanisms underlying senescence. Classical theories argue that high levels of extrinsic mortality should select for the evolution of shorter lifespans and earlier peak fertility. Non-classical theories, in contrast, posit that an increase in extrinsic mortality could select for the evolution of longer lifespans. Although numerous studies support the classical paradigm, recent data challenge classical predictions, finding that high extrinsic mortality can select for the evolution of longer lifespans. To further elucidate the role of extrinsic mortality in the evolution of aging, we implemented a stochastic, agent-based, computational model. We used a simulated annealing optimization approach to predict which model parameters predispose populations to evolve longer or shorter lifespans in response to increased levels of predation. We report that longer lifespans evolved in the presence of rising predation if the cost of mating is relatively high and if energy is available in excess. Conversely, we found that dramatically shorter lifespans evolved when mating costs were relatively low and food was relatively scarce. We also analyzed the effects of increased predation on various parameters related to density dependence and energy allocation. Longer and shorter lifespans were accompanied by increased and decreased investments of energy into somatic maintenance, respectively. Similarly, earlier and later maturation ages were accompanied by increased and decreased energetic investments into early fecundity, respectively. Higher predation significantly decreased the total population size, enlarged the shared resource pool, and redistributed energy reserves for mature individuals. These results both corroborate and refine classical predictions, demonstrating a population-level trade-off between longevity and fecundity and identifying conditions that produce both classical and non-classical lifespan effects. PMID:24466165

Statistical Metamodeling and Sequential Design of Computer Experiments to Model Glyco-Altered Gating of Sodium Channels in Cardiac Myocytes.

PubMed

Du, Dongping; Yang, Hui; Ednie, Andrew R; Bennett, Eric S

2016-09-01

Glycan structures account for up to 35% of the mass of cardiac sodium ( Nav ) channels. To question whether and how reduced sialylation affects Nav activity and cardiac electrical signaling, we conducted a series of in vitro experiments on ventricular apex myocytes under two different glycosylation conditions, reduced protein sialylation (ST3Gal4(-/-)) and full glycosylation (control). Although aberrant electrical signaling is observed in reduced sialylation, realizing a better understanding of mechanistic details of pathological variations in INa and AP is difficult without performing in silico studies. However, computer model of Nav channels and cardiac myocytes involves greater levels of complexity, e.g., high-dimensional parameter space, nonlinear and nonconvex equations. Traditional linear and nonlinear optimization methods have encountered many difficulties for model calibration. This paper presents a new statistical metamodeling approach for efficient computer experiments and optimization of Nav models. First, we utilize a fractional factorial design to identify control variables from the large set of model parameters, thereby reducing the dimensionality of parametric space. Further, we develop the Gaussian process model as a surrogate of expensive and time-consuming computer models and then identify the next best design point that yields the maximal probability of improvement. This process iterates until convergence, and the performance is evaluated and validated with real-world experimental data. Experimental results show the proposed algorithm achieves superior performance in modeling the kinetics of Nav channels under a variety of glycosylation conditions. As a result, in silico models provide a better understanding of glyco-altered mechanistic details in state transitions and distributions of Nav channels. Notably, ST3Gal4(-/-) myocytes are shown to have higher probabilities accumulated in intermediate inactivation during the repolarization and yield a shorter refractory period than WTs. The proposed statistical design of computer experiments is generally extensible to many other disciplines that involve large-scale and computationally expensive models.

Comparing the demands of destination entry using Google Glass and the Samsung Galaxy S4 during simulated driving.

PubMed

Beckers, Niek; Schreiner, Sam; Bertrand, Pierre; Mehler, Bruce; Reimer, Bryan

2017-01-01

The relative impact of using a Google Glass based voice interface to enter a destination address compared to voice and touch-entry methods using a handheld Samsung Galaxy S4 smartphone was assessed in a driving simulator. Voice entry (Google Glass and Samsung) had lower subjective workload ratings, lower standard deviation of lateral lane position, shorter task durations, faster remote Detection Response Task (DRT) reaction times, lower DRT miss rates, and resulted in less time glancing off-road than the primary visual-manual interaction with the Samsung Touch interface. Comparing voice entry methods, using Google Glass took less time, while glance metrics and reaction time to DRT events responded to were similar. In contrast, DRT miss rate was higher for Google Glass, suggesting that drivers may be under increased distraction levels but for a shorter period of time; whether one or the other equates to an overall safer driving experience is an open question. Copyright © 2016 Elsevier Ltd. All rights reserved.

Patient navigation reduces time to care for patients with breast symptoms and abnormal screening mammograms.

PubMed

McKevitt, Elaine; Dingee, Carol; Warburton, Rebecca; Pao, Jin-Si; Brown, Carl J; Wilson, Christine; Kuusk, Urve

2018-05-01

Concern has been raised about delays for patients presenting with breast symptoms in Canada. Our objective was to determine if our Rapid Access Breast Clinic (RABC) improved care for patients presenting with breast symptoms compared to the traditional system (TS). A retrospective chart review tabulated demographic, surgical, pathology and radiologic information. Wait times to care were determined for patients presenting with symptomatic and screen detected breast problems. Time from presentation to surgeon evaluation was shorter in the RABC group for patients with breast symptoms (81 vs 35 days, p < .0001) and abnormal screens (72 vs 40 days, p = .092). Cancer patients with abnormal screens had shorter wait times than patients with breast symptoms in the TS (47 vs 70 days, p = .036). Coordination of imaging and clinical care reduces wait times in patients with both abnormal screening mammograms and symptomatic breast presentations and should be expanded in our province. Copyright © 2018 Elsevier Inc. All rights reserved.

The level and nature of autistic intelligence III: Inspection time.

PubMed

Barbeau, Elise B; Soulières, Isabelle; Dawson, Michelle; Zeffiro, Thomas A; Mottron, Laurent

2013-02-01

Across the autism spectrum, level of intelligence is highly dependent on the psychometric instrument used for assessment, and there are conflicting views concerning which measures best estimate autistic cognitive abilities. Inspection time is a processing speed measure associated with general intelligence in typical individuals. We therefore investigated autism spectrum performance on inspection time in relation to two different general intelligence tests. Autism spectrum individuals were divided into autistic and Asperger subgroups according to speech development history. Compared to a typical control group, mean inspection time for the autistic subgroup but not the Asperger subgroup was significantly shorter (by 31%). However, the shorter mean autistic inspection time was evident only when groups were matched on Wechsler IQ and disappeared when they were matched using Raven's Progressive Matrices. When autism spectrum abilities are compared to typical abilities, results may be influenced by speech development history as well as by the instrument used for intelligence matching. 2013 APA, all rights reserved

Point prevalence of access block and overcrowding in New Zealand emergency departments in 2010 and their relationship to the 'Shorter Stays in ED' target.

PubMed

Jones, Peter G; Olsen, Sarah

2011-10-01

To document the extent of access block and ED overcrowding in New Zealand in 2010 and to determine whether these were linked to the hospital's ability to meet the Shorter Stays in ED target. Surveys of all New Zealand EDs were undertaken at two points in time in 2010 to determine ED occupancy. Data on target achievement during corresponding time periods were obtained from the Ministry of Health. In tertiary and secondary hospitals, respectively, access block was seen in 64% versus 23% (P= 0.05) and overcrowding was seen in 57.1% versus 39% (P= 0.45). No hospital with access block met the 'Shorter Stays' target, compared with 60% without access block (P= 0.001). Twenty-three per cent of hospitals with ED overcrowding met the target compared with 43% without ED overcrowding (P= 0.42). The number of patients experiencing ≥8 h delay to admission were 25 in May and 59 in August (P= 0.04). This represented 45.5% and 79.7% of patients waiting for admission, respectively (P= 0.08). Hospital access block was seen more often in larger hospitals and significantly associated with failure to meet the 'Shorter Stays in ED' health target, whereas ED overcrowding was seen in both small and large hospitals, but not associated with failure to meet the target. © 2011 The Authors. EMA © 2011 Australasian College for Emergency Medicine and Australasian Society for Emergency Medicine.

Effect of portal access system and surgery type on surgery times during laparoscopic ovariectomy and salpingectomy in captive African lions and cheetahs.

PubMed

Hartman, Marthinus Jacobus; Monnet, Eric; Kirberger, Robert Murco; Schoeman, Johan Petrus

2016-03-02

A prospective randomized study was used to compare surgery times for laparoscopic ovariectomy and salpingectomy in female African lion (Panthera leo) (n = 14) and cheetah (Acinonyx jubatus) (n = 20) and to compare the use of a multiple portal access system (MPAS) and single portal access system (SPAS) between groups. Two different portal techniques were used, namely MPAS (three separate ports) in lions and SPAS (SILS™ port) in cheetahs, using standard straight laparoscopic instruments. Portal access system and first ovary was not randomized. Five different surgery times were compared for the two different procedures as well as evaluating the use and application of MPAS and SPAS. Carbon dioxide volumes for lions were recorded. In adult lionesses operative time (OPT) (P = 0.016) and total surgical time (TST) (P = 0.032) were significantly shorter for salpingectomy compared to ovariectomy. Similarly in cheetahs OPT (P = 0.001) and TST (P = 0.005) were also shorter for salpingectomy compared to ovariectomy. In contrast, in lion cubs no difference was found in surgery times for ovariectomy and salpingectomy. Total unilateral procedure time was shorter than the respective bilateral time for both procedures (P = 0.019 and P = 0.001) respectively and unilateral salpingectomy was also faster than unilateral ovariectomy (P = 0.035) in cheetahs. Port placement time, suturing time and TST were significantly shorter for SPAS compared to MPAS (P = 0.008). There was, however, no difference in OPT between SPAS and MPAS. Instrument cluttering with SPAS was found to be negligible. There was no difference in mean volume CO2 required to complete ovariectomy in lions but the correlation between bodyweight and total volume of CO2 in lions was significant (rs = 0.867; P = 0.002). Laparoscopic salpingectomy was faster than ovariectomy in both adult lions and cheetahs. Using SPAS, both unilateral procedures were faster than bilateral procedures in cheetahs. Placement and suturing of SPAS in cheetahs was easier and faster compared to three separate ports in lions and lion cubs. The use of standard straight instruments during SPAS did not prolong surgery. Surgery was faster in cubs and CO2 required for laparoscopic sterilization in lions could be determined. Predictable surgery times and CO2 volumes will facilitate the accurate planning and execution of surgery in lions and cheetahs.

Common Atrial Fibrillation Risk Alleles at 4q25 Predict Recurrence after Catheter-based Atrial Fibrillation Ablation

PubMed Central

Shoemaker, M. Benjamin; Muhammad, Raafia; Parvez, Babar; White, Brenda W.; Streur, Megan; Song, Yanna; Stubblefield, Tanya; Kucera, Gayle; Blair, Marcia; Rytlewski, Jason; Parvathaneni, Sunthosh; Nagarakanti, Rangadham; Saavedra, Pablo; Ellis, Christopher; Whalen, S. Patrick; Roden, Dan M; Darbar, Dawood

2012-01-01

Background Common single nucleotide polymorphisms (SNPs) at chromosome 4q25 (rs2200733, rs10033464) are associated with both lone and typical AF. Risk alleles at 4q25 have recently been shown to predict recurrence of AF after ablation in a population of predominately lone AF, but lone AF represents only 5–30% of AF cases. Objective To test the hypothesis that 4q25 AF risk alleles can predict response to AF ablation in the majority of AF cases. Methods Patients enrolled in the Vanderbilt AF Registry underwent 378 catheter-based AF ablations (median age 60 years, 71% male, 89% typical AF) between 2004 and 2011. The primary endpoint was time to recurrence of any non-sinus atrial tachyarrhythmia (atrial tachycardia, atrial flutter, or AF; [AT/AF]). Results Two-hundred AT/AF recurrences (53%) were observed. In multivariable analysis, the rs2200733 risk allele predicted a 24% shorter recurrence-free time (survival time ratio 0.76 95% confidence interval [CI] 0.6–0.95, P=0.016) compared with wild-type. The heterozygous haplotype demonstrated a 21% shorter recurrence-free time (survival time ratio = 0.79, 95% CI 0.62–0.99) and the homozygous risk allele carriers a 39% shorter recurrence-free time (survival time ratio = 0.61, 95% CI 0.37–1.0) (P=0.037). Conclusion Risk alleles at the 4q25 loci predict impaired clinical response to AF ablation in a population of predominately typical AF patients. Our findings suggest the rs2200733 polymorphism may hold promise as an as an objectively measured patient characteristic that can used as a clinical tool for selection of patients for AF ablation. PMID:23178686

Improving Crotalidae polyvalent immune Fab reconstitution times.

PubMed

Quan, Asia N; Quan, Dan; Curry, Steven C

2010-06-01

Crotalidae polyvalent immune Fab (CroFab) is used to treat rattlesnake envenomations in the United States. Time to infusion may be a critical factor in the treatment of these bites. Per manufacturer's instructions, 10 mL of sterile water for injection (SWI) and hand swirling are recommended for reconstitution. We wondered whether completely filling vials with 25 mL of SWI would result in shorter reconstitution times than using 10-mL volumes and how hand mixing compared to mechanical agitation of vials or leaving vials undisturbed. Six sets of 5 vials were filled with either 10 mL or 25 mL. Three mixing techniques were used as follows: undisturbed; agitation with a mechanical agitator; and continuous hand rolling and inverting of vials. Dissolution was determined by observation and time to complete dissolution for each vial. Nonparametric 2-tailed P values were calculated. Filling vials completely with 25 mL resulted in quicker dissolution than using 10-mL volumes, regardless of mixing method (2-tailed P = .024). Mixing by hand was shorter than other methods (P < .001). Reconstitution with 25 mL and hand mixing resulted in the shortest dissolution times (median, 1.1 minutes; range, 0.9-1.3 minutes). This appeared clinically important because dissolution times using 10 mL and mechanical rocking of vials (median, 26.4 minutes) or leaving vials undisturbed (median, 33.6 minutes) was several-fold longer. Hand mixing after filling vials completely with 25 mL results in shorter dissolution times than using 10 mL or other methods of mixing and is recommended, especially when preparing initial doses of CroFab. Copyright (c) 2010 Elsevier Inc. All rights reserved.

Patient navigation significantly reduces delays in breast cancer diagnosis in the District of Columbia.

PubMed

Hoffman, Heather J; LaVerda, Nancy L; Young, Heather A; Levine, Paul H; Alexander, Lisa M; Brem, Rachel; Caicedo, Larisa; Eng-Wong, Jennifer; Frederick, Wayne; Funderburk, William; Huerta, Elmer; Swain, Sandra; Patierno, Steven R

2012-10-01

Patient Navigation (PN) originated in Harlem as an intervention to help poor women overcome access barriers to timely breast cancer treatment. Despite rapid, nationally widespread adoption of PN, empirical evidence on its effectiveness is lacking. In 2005, National Cancer Institute initiated a multicenter PN Research Program (PNRP) to measure PN effectiveness for several cancers. The George Washington Cancer Institute, a project participant, established District of Columbia (DC)-PNRP to determine PN's ability to reduce breast cancer diagnostic time (number of days from abnormal screening to definitive diagnosis). A total of 2,601 women (1,047 navigated; 1,554 concurrent records-based nonnavigated) were examined for breast cancer from 2006 to 2010 at 9 hospitals/clinics in DC. Analyses included only women who reached complete diagnostic resolution. Differences in diagnostic time between navigation groups were tested with ANOVA models including categorical demographic and treatment variables. Log transformations normalized diagnostic time. Geometric means were estimated and compared using Tukey-Kramer P value adjustments. Average-geometric mean [95% confidence interval (CI)]-diagnostic time (days) was significantly shorter for navigated, 25.1 (21.7, 29.0), than nonnavigated women, 42.1 (35.8, 49.6). Subanalyses revealed significantly shorter average diagnostic time for biopsied navigated women, 26.6 (21.8, 32.5) than biopsied nonnavigated women, 57.5 (46.3, 71.5). Among nonbiopsied women, diagnostic time was shorter for navigated, 27.2 (22.8, 32.4), than nonnavigated women, 34.9 (29.2, 41.7), but not statistically significant. Navigated women, especially those requiring biopsy, reached their diagnostic resolution significantly faster than nonnavigated women. Results support previous findings of PN's positive influence on health care. PN should be a reimbursable expense to assure continuation of PN programs. 2012 AACR

Utilization of Total Joint Arthroplasty in Physician-Owned Specialty Hospitals vs Acute Care Facilities.

PubMed

Chen, Antonia F; Pflug, Emily; O'Brien, Daniel; Maltenfort, Mitchell G; Parvizi, Javad

2017-07-01

The recent emergence of physician-owned specialty hospitals has sparked controversy about overutilization. Thus, the purpose of this study was to compare utilization patterns of total joint arthroplasty (TJA) between physician-specialty hospitals (PSHs) and acute care hospitals (ACHs). A retrospective study was conducted from January 2010 to August 2014 comparing primary TJA patients between a PSH and an ACH; 103 PSH patients were matched to 103 ACH patients by age, gender, BMI, and ASA classification with similar case distribution between facilities. All surgeons in the study operated at both hospitals and were shareholders of the PSH. Information on nonoperative treatments, and timing to the initial appointment, consent, and surgery were analyzed using univariate analysis. Nonoperative treatments before surgery were similar between hospitals (P = 1.00). The time from the initial appointment to consent was longer for PSH (P = .0001). However, the time from consent to the date of surgery (P = .04) and the timing from symptoms to initial appointment (P = .006) was shorter for PSH. The time from initial appointment to the day of surgery was similar between groups (P = .20). Patients were more likely to be consented for surgery on their first clinic visit when undergoing surgery at ACH (87 of 103, 84.4%) compared to PSH (61 of 103; 59.2%; P < .001). Length of stay was significantly shorter for both total knee arthroplasty (P = .001) and total hip arthroplasty patients (P = .001) at PSH. Facility ownership in PSH resulted in similar conservative treatment before TJA. The time to surgical consent after the initial appointment was longer PSH, whereas the time from consent to the date of surgery was shorter at the PSH. Copyright © 2017 Elsevier Inc. All rights reserved.

Working Less and Enjoying It More: Alternative Work Schedules.

ERIC Educational Resources Information Center

Shanks, Katherine

1984-01-01

Explores three forms of alternative work schedules that research has shown improve job performance and decrease absenteeism: flextime (starting and stopping times vary within limits); permanent part-time employment (regular employment carried out during shorter working hours); and job sharing (two or more part-time employees share one full-time…

Development of AN Innovative Three-Dimensional Complete Body Screening Device - 3D-CBS

NASA Astrophysics Data System (ADS)

Crosetto, D. B.

2004-07-01

This article describes an innovative technological approach that increases the efficiency with which a large number of particles (photons) can be detected and analyzed. The three-dimensional complete body screening (3D-CBS) combines the functional imaging capability of the Positron Emission Tomography (PET) with those of the anatomical imaging capability of Computed Tomography (CT). The novel techniques provide better images in a shorter time with less radiation to the patient. A primary means of accomplishing this is the use of a larger solid angle, but this requires a new electronic technique capable of handling the increased data rate. This technique, combined with an improved and simplified detector assembly, enables executing complex real-time algorithms and allows more efficiently use of economical crystals. These are the principal features of this invention. A good synergy of advanced techniques in particle detection, together with technological progress in industry (latest FPGA technology) and simple, but cost-effective ideas provide a revolutionary invention. This technology enables over 400 times PET efficiency improvement at once compared to two to three times improvements achieved every five years during the past decades. Details of the electronics are provided, including an IBM PC board with a parallel-processing architecture implemented in FPGA, enabling the execution of a programmable complex real-time algorithm for best detection of photons.

An adaptive incremental approach to constructing ensemble classifiers: application in an information-theoretic computer-aided decision system for detection of masses in mammograms.

PubMed

Mazurowski, Maciej A; Zurada, Jacek M; Tourassi, Georgia D

2009-07-01

Ensemble classifiers have been shown efficient in multiple applications. In this article, the authors explore the effectiveness of ensemble classifiers in a case-based computer-aided diagnosis system for detection of masses in mammograms. They evaluate two general ways of constructing subclassifiers by resampling of the available development dataset: Random division and random selection. Furthermore, they discuss the problem of selecting the ensemble size and propose two adaptive incremental techniques that automatically select the size for the problem at hand. All the techniques are evaluated with respect to a previously proposed information-theoretic CAD system (IT-CAD). The experimental results show that the examined ensemble techniques provide a statistically significant improvement (AUC = 0.905 +/- 0.024) in performance as compared to the original IT-CAD system (AUC = 0.865 +/- 0.029). Some of the techniques allow for a notable reduction in the total number of examples stored in the case base (to 1.3% of the original size), which, in turn, results in lower storage requirements and a shorter response time of the system. Among the methods examined in this article, the two proposed adaptive techniques are by far the most effective for this purpose. Furthermore, the authors provide some discussion and guidance for choosing the ensemble parameters.

Comparison of transcatheter aortic valve and surgical bioprosthetic valve durability: a fatigue simulation study

PubMed Central

Martin, Caitlin; Sun, Wei

2015-01-01

Transcatheter aortic valve (TAV) intervention is now the standard-of-care treatment for inoperable patients and a viable alternative treatment option for high-risk patients with symptomatic aortic stenosis. While the procedure is associated with lower operative risk and shorter recovery times than traditional surgical aortic valve (SAV) replacement, TAV intervention is still not considered for lower-risk patients due in part to concerns about device durability. It is well known that bioprosthetic SAVs have limited durability, and TAVs are generally assumed to have even worse durability, yet there is little long-term data to confirm this suspicion. In this study, TAV and SAV leaflet fatigue due to cyclic loading was investigated through finite element analysis by implementing a computational soft tissue fatigue damage model to describe the behavior of the pericardial leaflets. Under identical loading conditions and with identical leaflet tissue properties, the TAV leaflets sustained higher stresses, strains, and fatigue damage compared to the SAV leaflets. The simulation results suggest that the durability of TAVs may be significantly reduced compared to SAVs to about 7.8 years. The developed computational framework may be useful in optimizing TAV design parameters to improve leaflet durability, and assessing the effects of underexpanded, elliptical, or non-uniformly expanded stent deployment on TAV durability. PMID:26294354

Postcollapse Evolution of Globular Clusters

NASA Astrophysics Data System (ADS)

Makino, Junichiro

1996-11-01

A number of globular clusters appear to have undergone core collapse, in the sense that their predicted collapse times are much shorter than their current ages. Simulations with gas models and the Fokker-Planck approximation have shown that the central density of a globular cluster after the collapse undergoes nonlinear oscillation with a large amplitude (gravothermal oscillation). However, the question whether such an oscillation actually takes place in real N-body systems has remained unsolved because an N-body simulation with a sufficiently high resolution would have required computing resources of the order of several GFLOPS-yr. In the present paper, we report the results of such a simulation performed on a dedicated special-purpose computer, GRAPE-4. We have simulated the evolution of isolated point-mass systems with up to 32,768 particles. The largest number of particles reported previously is 10,000. We confirm that gravothermal oscillation takes place in an N-body system. The expansion phase shows all the signatures that are considered to be evidence of the gravothermal nature of the oscillation. At the maximum expansion, the core radius is ˜1% of the half-mass radius for the run with 32,768 particles. The maximum core size, rc, depends on N as ∝ N-1/3.

Prognostic significance of tumor histology and computed tomographic staging for radiation treatment response of canine nasal tumors.

PubMed

Adams, William M; Kleiter, Miriam M; Thrall, Donald E; Klauer, Julia M; Forrest, Lisa J; La Due, Tracy A; Havighurst, Thomas C

2009-01-01

Prognostic significance of tumor histology and four computed tomography (CT) staging methods was tested retrospectively in dogs from three treatment centers that underwent intent-to-cure-radiotherapy for intranasal neoplasia. Disease-free and overall survival times were available for 94 dogs. A grouping of anaplastic, squamous cell, and undifferentiated carcinomas had a significantly shorter median disease-free survival (4.4 mo) than a grouping of all sarcomas (10.6 months). Disease-free survivals were not significantly different, when all carcinomas were compared with all sarcomas. The published original and modified WHO staging methods did not significantly relate to either survival endpoint. A modified human maxillary tumor staging system previously applied to canine nasal tumors was prognostically significant for both survival endpoints; a further modified version of that CT-based staging system resulted in improved significance for both survival endpoints. Dogs with unilateral intranasal involvement without bone destruction beyond the turbinates on CT, had longest median survival (23.4 months); CT evidence of cribriform plate involvement was associated with shortest median survival (6.7 months). Combining CT and histology statistically improved prognostic significance for both survival endpoints over the proposed CT staging method alone. Significance was lost when CT stages were collapsed to < four categories or histopathology groupings were collapsed to < three categories.

EAO Supplement Working Group 4 - EAO CC 2015 Short implants versus sinus lifting with longer implants to restore the posterior maxilla: a systematic review.

PubMed

Thoma, D S; Zeltner, M; Hüsler, J; Hämmerle, C H F; Jung, R E

2015-09-01

To compare short implants in the posterior maxilla to longer implants placed after or simultaneously with sinus floor elevation procedures. The focused question was as follows: Are short implants superior to longer implants in the augmented sinus in terms of survival and complication rates of implants and reconstructions, patient-reported outcome measures (PROMs) and costs? A MEDLINE search (1990-2014) was performed for randomized controlled clinical studies comparing short implants (≤8 mm) to longer implants (>8 mm) in augmented sinus. The search was complimented by an additional hand search of the selected papers and reviews published between 2011 and 2014. Eligible studies were selected based on the inclusion criteria, and quality assessments were conducted. Descriptive statistics were applied for a number of outcome measures. Survival rates of dental implants were pooled simply in case of comparable studies. Eight randomized controlled clinical trials (RCTs) comparing short implants versus longer implants in the augmented sinus derived from an initial search count of 851 titles were selected and data extracted. In general, all studies were well conducted with a low risk of bias for the majority of the analyzed parameters. Based on the pooled analyses of longer follow-ups (5 studies, 16-18 months), the survival rate of longer implants amounted to 99.5% (95% CI: 97.6-99.98%) and for shorter implants to 99.0% (95% CI: 96.4-99.8%). For shorter follow-ups (3 studies, 8-9 months), the survival rates of longer implants are 100% (95% CI: 97.1-100%) and for shorter implants 98.2% (95% CI: 93.9-99.7%). Complications were predominantly of biological origin, mainly occurred intraoperatively as membrane perforations, and were almost three times as higher for longer implant in the augmented sinus compared to shorter implants. PROMs, morbidity, surgical time and costs were generally in favor of shorter dental implants. All studies were performed by surgeons in specialized clinical settings. The outcomes of the survey analyses demonstrated predictably high implant survival rates for short implants and longer implants placed in augmented sinus and their respective reconstructions. Given the higher number of biological complications, increased morbidity, costs and surgical time of longer dental implants in the augmented sinus, shorter dental implants may represent the preferred treatment alternative. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

May radiofrequency be the best choice for III-IV degree hemorrhoids?

PubMed

Milito, Giovanni; Lisi, Giorgio; Aronadio, Elena; Campanelli, Michela; Venditti, Dario; Grande, Simona; Grande, Michele

2017-03-01

Hemorrhoidectomy is considered the most efficient method to treat hemorrhoids of III and IV grades. The aim of this study was to compare conventional diathermy hemorrhoidectomy and radiofrequency hemorrhoidectomy based on a large series of patients. Between June 2001 and June 2014, 1000 patients have been treated with radiofrequency hemorrhoidectomy (group A) and 500 patients have been treated with diathermy (group B) as a day-case procedure. Operating time, postoperative pain score, hospital stay, early and late postoperative complications, wound healing time and time to return to normal activities were assessed. The mean follow-up was seven years. The mean operating time for radiofrequency hemorrhoidectomy was shorter than diathermy but not significantly. Patients treated with radiofrequency had significantly less postoperative pain (measured on a Visual Analogue Scale; P=0.001), a shorter wound healing time, less time off work and postoperative complications (P=0.001) than patients who had diathermy. Neither wound healing nor mean hospital stay (day-case surgery) was significantly different. Radiofrequency hemorrhoidectomyis a valid alternative to the conventional diathermy technique, due to the reduction of operative time, postoperative pain, early and late complication rate.

Foot strike patterns and ground contact times during high-calibre middle-distance races.

PubMed

Hayes, Phil; Caplan, Nicholas

2012-01-01

The aims of this study were to examine ground contact characteristics, their relationship with race performance, and the time course of any changes in ground contact time during competitive 800 m and 1500 m races. Twenty-two seeded, single-sex middle-distance races totalling 181 runners were filmed at a competitive athletics meeting. Races were filmed at 100 Hz. Ground contact time was recorded one step for each athlete, on each lap of their race. Forefoot and midfoot strikers had significantly shorter ground contact times than heel strikers. Forefoot and midfoot strikers had significantly faster average race speed than heel strikers. There were strong large correlations between ground contact time and average race speed for the women's events and men's 1500 m (r = -0.521 to -0.623; P < 0.05), whereas the men's 800 m displayed only a moderate relationship (r = -0.361; P = 0.002). For each event, ground contact time for the first lap was significantly shorter than for the last lap, which might reflect runners becoming fatigued.

Longitudinal associations between time spent using technology and sleep duration among adolescents.

PubMed

Mazzer, K; Bauducco, S; Linton, S J; Boersma, K

2018-07-01

Technology use has been the focus of much concern for adolescents' sleep health. However, few studies have investigated the bidirectional association between sleep duration and time spent using technology. The aim of this study was to test whether time spent using technology predicted shorter sleep duration, and/or vice versa using cross-lagged analyses over one year. Participants were 1620 high school students in the 8th and 9th grade at baseline from 17 public schools in three middle Sweden communities. Students completed questionnaires at school during the spring of 2015 and 2016. Time spent using technology was self-reported and sleep duration was calculated from reported bed-times, wake-times and sleep onset latency. Time spent using technology significantly predicted shorter subsequent sleep duration and vice versa. Public health advocates educating others about the negative impacts of technology on sleep must also be mindful of the opposite, that many young people may turn to technological devices when experiencing difficulty sleeping. Copyright © 2018 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

Reflection characterization of nano-sized dielectric structure in Morpho butterfly wings

NASA Astrophysics Data System (ADS)

Zhu, Dong

2017-10-01

Morpho butterflies living in Central and South America are well-known for their structural-colored blue wings. The blue coloring originates from the interaction of light with nano-sized dielectric structures that are equipped on the external surface of scales covering over their wings. The high-accuracy nonstandard finite-difference time domain (NS-FDTD) method is used to investigate the reflection characterization from the nanostructures. In the NS-FDTD calculation, a computational model is built to mimic the actual tree-like multilayered structures wherever possible using the hyperbolic tangent functions. It is generally known that both multilayer interference and diffraction grating phenomena can occur when light enters the nano-sized multilayered structure. To answer the question that which phenomenon is mainly responsible for the blue coloring, the NS-FDTD calculation is performed under various incidence angles at wavelengths from 360 to 500 nm. The calculated results at one incident wavelength under different incidence angles are visualized in a two-dimensional mapping image, where horizontal and vertical axes are incidence and reflection angles, respectively. The images demonstrate a remarkable transition from a ring-like pattern at shorter wavelengths to a retro-reflection pattern at longer wavelengths. To clarify the origin of the pattern transition, the model is separated into several simpler parts and compared their mapping images with the theoretical diffraction calculations. It can be concluded that the blue coloring at longer wavelengths is mainly caused by the cooperation of multilayer interference and retro-reflection while the effect of diffraction grating is predominant at shorter wavelengths.

Long pulse production from short pulses

DOEpatents

Toeppen, J.S.

1994-08-02

A method of producing a long output pulse from a short pump pulse is disclosed, using an elongated amplified fiber having a doped core that provides an amplifying medium for light of one color when driven into an excited state by light of a shorter wavelength and a surrounding cladding. A seed beam of the longer wavelength is injected into the core at one end of the fiber and a pump pulse of the shorter wavelength is injected into the cladding at the other end of the fiber. The counter-propagating seed beam and pump pulse will produce an amplified output pulse having a time duration equal to twice the transit time of the pump pulse through the fiber plus the length of the pump pulse. 3 figs.

Missile signal processing common computer architecture for rapid technology upgrade

NASA Astrophysics Data System (ADS)

Rabinkin, Daniel V.; Rutledge, Edward; Monticciolo, Paul

2004-10-01

Interceptor missiles process IR images to locate an intended target and guide the interceptor towards it. Signal processing requirements have increased as the sensor bandwidth increases and interceptors operate against more sophisticated targets. A typical interceptor signal processing chain is comprised of two parts. Front-end video processing operates on all pixels of the image and performs such operations as non-uniformity correction (NUC), image stabilization, frame integration and detection. Back-end target processing, which tracks and classifies targets detected in the image, performs such algorithms as Kalman tracking, spectral feature extraction and target discrimination. In the past, video processing was implemented using ASIC components or FPGAs because computation requirements exceeded the throughput of general-purpose processors. Target processing was performed using hybrid architectures that included ASICs, DSPs and general-purpose processors. The resulting systems tended to be function-specific, and required custom software development. They were developed using non-integrated toolsets and test equipment was developed along with the processor platform. The lifespan of a system utilizing the signal processing platform often spans decades, while the specialized nature of processor hardware and software makes it difficult and costly to upgrade. As a result, the signal processing systems often run on outdated technology, algorithms are difficult to update, and system effectiveness is impaired by the inability to rapidly respond to new threats. A new design approach is made possible three developments; Moore's Law - driven improvement in computational throughput; a newly introduced vector computing capability in general purpose processors; and a modern set of open interface software standards. Today's multiprocessor commercial-off-the-shelf (COTS) platforms have sufficient throughput to support interceptor signal processing requirements. This application may be programmed under existing real-time operating systems using parallel processing software libraries, resulting in highly portable code that can be rapidly migrated to new platforms as processor technology evolves. Use of standardized development tools and 3rd party software upgrades are enabled as well as rapid upgrade of processing components as improved algorithms are developed. The resulting weapon system will have a superior processing capability over a custom approach at the time of deployment as a result of a shorter development cycles and use of newer technology. The signal processing computer may be upgraded over the lifecycle of the weapon system, and can migrate between weapon system variants enabled by modification simplicity. This paper presents a reference design using the new approach that utilizes an Altivec PowerPC parallel COTS platform. It uses a VxWorks-based real-time operating system (RTOS), and application code developed using an efficient parallel vector library (PVL). A quantification of computing requirements and demonstration of interceptor algorithm operating on this real-time platform are provided.

Travel time and concurrent-schedule choice: retrospective versus prospective control.

PubMed

Davison, M; Elliffe, D

2000-01-01

Six pigeons were trained on concurrent variable-interval schedules in which two different travel times between alternatives, 4.5 and 0.5 s, were randomly arranged. In Part 1, the next travel time was signaled while the subjects were responding on each alternative. Generalized matching analyses of performance in the presence of the two travel-time signals showed significantly higher response and time sensitivity when the longer travel time was signaled compared to when the shorter time was signaled. When the data were analyzed as a function of the previous travel time, there were no differences in sensitivity. Dwell times on the alternatives were consistently longer in the presence of the stimulus that signaled the longer travel time than they were in the presence of the stimulus that signaled the shorter travel time. These results are in accord with a recent quantitative account of the effects of travel time. In Part 2, no signals indicating the next travel time were given. When these data were analyzed as a function of the previous travel time, time-allocation sensitivity after the 4.5-s travel time was significantly greater than that after the 0.5-s travel time, but no such difference was found for response allocation. Dwell times were also longer when the previous travel time had been longer.

Reproducing Quantum Probability Distributions at the Speed of Classical Dynamics: A New Approach for Developing Force-Field Functors.

PubMed

Sundar, Vikram; Gelbwaser-Klimovsky, David; Aspuru-Guzik, Alán

2018-04-05

Modeling nuclear quantum effects is required for accurate molecular dynamics (MD) simulations of molecules. The community has paid special attention to water and other biomolecules that show hydrogen bonding. Standard methods of modeling nuclear quantum effects like Ring Polymer Molecular Dynamics (RPMD) are computationally costlier than running classical trajectories. A force-field functor (FFF) is an alternative method that computes an effective force field that replicates quantum properties of the original force field. In this work, we propose an efficient method of computing FFF using the Wigner-Kirkwood expansion. As a test case, we calculate a range of thermodynamic properties of Neon, obtaining the same level of accuracy as RPMD, but with the shorter runtime of classical simulations. By modifying existing MD programs, the proposed method could be used in the future to increase the efficiency and accuracy of MD simulations involving water and proteins.

Childhood sleep and adolescent chronic fatigue syndrome (CFS/ME): evidence of associations in a UK birth cohort.

PubMed

Collin, Simon M; Norris, Tom; Gringras, Paul; Blair, Peter S; Tilling, Kate; Crawley, Esther

2018-06-01

Sleep abnormalities are characteristic of chronic fatigue syndrome (CFS, also known as 'ME'), however it is unknown whether sleep might be a causal risk factor for CFS/ME. We analysed data from the Avon Longitudinal Study of Parents and Children (ALSPAC) birth cohort. We describe sleep patterns of children aged 6 months to 11 years, who were subsequently classified as having (or not having) 'chronic disabling fatigue' (CDF, a proxy for CFS/ME) between the ages 13 and 18 years, and we investigated the associations of sleep duration at age nine years with CDF at age 13 years, as well as sleep duration at age 11 years with CDF at age 16 years. Children who had CDF during adolescence had shorter night-time sleep duration from 6 months to 11 years of age, and there was strong evidence that difficulties in going to sleep were more common in children who subsequently developed CDF. The odds of CDF at age 13 years were 39% lower (odds ratio (OR) = 0.61, 95% CI = 0.43, 0.88) for each additional hour of night-time sleep at age nine years, and the odds of CDF at age 16 years were 51% lower (OR = 0.49, 95% CI = 0.34, 0.70) for each additional hour of night-time sleep at age 11 years. Mean night-time sleep duration at age nine years was 13.9 (95% CI = 3.75, 24.0) minutes shorter among children who developed CDF at age 13 years, and sleep duration at age 11 years was 18.7 (95% CI = 9.08, 28.4) minutes shorter among children who developed CDF at age 16 (compared with children who did not develop CDF at 13 and 16 years, respectively). Children who develop chronic disabling fatigue in adolescence have shorter night-time sleep duration throughout early childhood, suggesting that sleep abnormalities may have a causal role in CFS/ME or that sleep abnormalities and CFS/ME are associated with a common pathophysiological cause. Copyright © 2018 The Author(s). Published by Elsevier B.V. All rights reserved.

Randomized, double-blind, placebo-controlled clinical trial of loperamide plus simethicone versus loperamide alone and simethicone alone in the treatment of acute diarrhea with gas-related abdominal discomfort.

PubMed

Hanauer, Stephen B; DuPont, Herbert L; Cooper, Kimberly M; Laudadio, Charles

2007-05-01

To compare efficacy and tolerability of a loperamide/simethicone (LOP/SIM) combination product with that of loperamide (LOP) alone, simethicone (SIM) alone, and placebo (PBO) for acute nonspecific diarrhea with gas-related abdominal discomfort. In this multicenter, double-blind, 48-h study, patients were randomly assigned to receive two tablets, each containing either LOP/SIM 2 mg/125 mg (n = 121), LOP 2 mg (n = 120), SIM 125 mg (n = 123), or PBO (n = 121), followed by one tablet after each unformed stool, up to four tablets in any 24-h period. The primary outcome measures were time to last unformed stool and time to complete relief of gas-related abdominal discomfort. For time to last unformed stool, an unformed stool after a 24-h period of formed stools or no stools was considered a continuance of the original episode (stricter definition) or a new episode (alternate definition). A total of 483 patients were included in the intent-to-treat analysis. The median time to last unformed stool for LOP/SIM (7.6 h) was significantly shorter than that of LOP (11.5 h), SIM (26.0 h), and PBO (29.4 h) (p < or = 0.0232 in comparison with survival curves) using the alternate definition; it was numerically but not significantly shorter than that of LOP (p = 0.0709) and significantly shorter than that of SIM and PBO (p = 0.0001) using the stricter definition. LOP/SIM-treated patients had a shorter time to complete relief of gas-related abdominal discomfort than patients who received either ingredient alone or placebo (all p = 0.0001). Few patients reported adverse events in the four treatment groups, none of which were serious in nature. Potential study limitations include the ability to generalize study results to the population at large, variability in total dose consumed, and subjectivity of patient diary data. LOP/SIM was well-tolerated and more efficacious than LOP alone, SIM alone, or placebo for acute nonspecific diarrhea and gas-related abdominal discomfort.

Standardizing clinical trials workflow representation in UML for international site comparison.

PubMed

de Carvalho, Elias Cesar Araujo; Jayanti, Madhav Kishore; Batilana, Adelia Portero; Kozan, Andreia M O; Rodrigues, Maria J; Shah, Jatin; Loures, Marco R; Patil, Sunita; Payne, Philip; Pietrobon, Ricardo

2010-11-09

With the globalization of clinical trials, a growing emphasis has been placed on the standardization of the workflow in order to ensure the reproducibility and reliability of the overall trial. Despite the importance of workflow evaluation, to our knowledge no previous studies have attempted to adapt existing modeling languages to standardize the representation of clinical trials. Unified Modeling Language (UML) is a computational language that can be used to model operational workflow, and a UML profile can be developed to standardize UML models within a given domain. This paper's objective is to develop a UML profile to extend the UML Activity Diagram schema into the clinical trials domain, defining a standard representation for clinical trial workflow diagrams in UML. Two Brazilian clinical trial sites in rheumatology and oncology were examined to model their workflow and collect time-motion data. UML modeling was conducted in Eclipse, and a UML profile was developed to incorporate information used in discrete event simulation software. Ethnographic observation revealed bottlenecks in workflow: these included tasks requiring full commitment of CRCs, transferring notes from paper to computers, deviations from standard operating procedures, and conflicts between different IT systems. Time-motion analysis revealed that nurses' activities took up the most time in the workflow and contained a high frequency of shorter duration activities. Administrative assistants performed more activities near the beginning and end of the workflow. Overall, clinical trial tasks had a greater frequency than clinic routines or other general activities. This paper describes a method for modeling clinical trial workflow in UML and standardizing these workflow diagrams through a UML profile. In the increasingly global environment of clinical trials, the standardization of workflow modeling is a necessary precursor to conducting a comparative analysis of international clinical trials workflows.

Standardizing Clinical Trials Workflow Representation in UML for International Site Comparison

PubMed Central

de Carvalho, Elias Cesar Araujo; Jayanti, Madhav Kishore; Batilana, Adelia Portero; Kozan, Andreia M. O.; Rodrigues, Maria J.; Shah, Jatin; Loures, Marco R.; Patil, Sunita; Payne, Philip; Pietrobon, Ricardo

2010-01-01

Background With the globalization of clinical trials, a growing emphasis has been placed on the standardization of the workflow in order to ensure the reproducibility and reliability of the overall trial. Despite the importance of workflow evaluation, to our knowledge no previous studies have attempted to adapt existing modeling languages to standardize the representation of clinical trials. Unified Modeling Language (UML) is a computational language that can be used to model operational workflow, and a UML profile can be developed to standardize UML models within a given domain. This paper's objective is to develop a UML profile to extend the UML Activity Diagram schema into the clinical trials domain, defining a standard representation for clinical trial workflow diagrams in UML. Methods Two Brazilian clinical trial sites in rheumatology and oncology were examined to model their workflow and collect time-motion data. UML modeling was conducted in Eclipse, and a UML profile was developed to incorporate information used in discrete event simulation software. Results Ethnographic observation revealed bottlenecks in workflow: these included tasks requiring full commitment of CRCs, transferring notes from paper to computers, deviations from standard operating procedures, and conflicts between different IT systems. Time-motion analysis revealed that nurses' activities took up the most time in the workflow and contained a high frequency of shorter duration activities. Administrative assistants performed more activities near the beginning and end of the workflow. Overall, clinical trial tasks had a greater frequency than clinic routines or other general activities. Conclusions This paper describes a method for modeling clinical trial workflow in UML and standardizing these workflow diagrams through a UML profile. In the increasingly global environment of clinical trials, the standardization of workflow modeling is a necessary precursor to conducting a comparative analysis of international clinical trials workflows. PMID:21085484

Impact of introduction of an acute surgical unit on management and outcomes of small bowel obstruction.

PubMed

Musiienko, Anton M; Shakerian, Rose; Gorelik, Alexandra; Thomson, Benjamin N J; Skandarajah, Anita R

2016-10-01

The acute surgical unit (ASU) is a recently established model of care in Australasia and worldwide. Limited data are available regarding its effect on the management of small bowel obstruction. We compared the management of small bowel obstruction before and after introduction of ASU at a major tertiary referral centre. We hypothesized that introduction of ASU would correlate with improved patient outcomes. A retrospective review of prospectively maintained databases was performed over two separate 2-year periods, before and after the introduction of ASU. Data collected included demographics, co-morbidity status, use of water-soluble contrast agent and computed tomography. Outcome measures included surgical intervention, time to surgery, hospital length of stay, complications, 30-day readmissions, use of total parenteral nutrition, intensive care unit admissions and overall mortality. Total emergency admissions to the ASU increased from 2640 to 4575 between the two time periods. A total of 481 cases were identified (225 prior and 256 after introduction of ASU). Mortality decreased from 5.8% to 2.0% (P = 0.03), which remained significant after controlling for confounders with multivariate analysis (odds ratio = 0.24, 95% confidence interval 0.08-0.73, P = 0.012). The proportion of surgically managed patients increased (20.9% versus 32.0%, P = 0.003) and more operations were performed within 5 days from presentation (76.6% versus 91.5%, P = 0.02). Fewer patients received water-soluble contrast agent (27.1% versus 18.4%, P = 0.02), but more patients were investigated with a computed tomography (70.7% versus 79.7%, P = 0.02). The ASU model of care resulted in decreased mortality, shorter time to intervention and increased surgical management. Overall complications rate and length of stay did not change. © 2015 Royal Australasian College of Surgeons.

Time-dependence of the holographic spectral function: diverse routes to thermalisation

DOE PAGES

Banerjee, Souvik; Ishii, Takaaki; Joshi, Lata Kh; ...

2016-08-08

Here, we develop a new method for computing the holographic retarded propagator in generic (non-) equilibrium states using the state/geometry map. We check that our method reproduces the thermal spectral function given by the Son-Starinets prescription. The time-dependence of the spectral function of a relevant scalar operator is studied in a class of non-equilibrium states. The latter are represented by AdS-Vaidya geometries with an arbitrary parameter characterising the timescale for the dual state to transit from an initial thermal equilibrium to another due to a homogeneous quench. For long quench duration, the spectral function indeed follows the thermal form atmore » the instantaneous effective temperature adiabatically, although with a slight initial time delay and a bit premature thermalisation. At shorter quench durations, several new non-adiabatic features appear: (i) time-dependence of the spectral function is seen much before than that in the effective temperature (advanced time-dependence), (ii) a big transfer of spectral weight to frequencies greater than the initial temperature occurs at an intermediate time (kink formation) and (iii) new peaks with decreasing amplitudes but in greater numbers appear even after the effective temperature has stabilised (persistent oscillations). We find four broad routes to thermalisation for lower values of spatial momenta. At higher values of spatial momenta, kink formations and persistent oscillations are suppressed, and thermalisation time decreases. The general thermalisation pattern is globally top-down, but a closer look reveals complexities.« less

Factors affecting breast cancer treatment delay in Turkey: a study from Turkish Federation of Breast Diseases Societies

PubMed Central

Boylu, Sukru; Ok, Engin; Canturk, Nuh Zafer; Celik, Varol; Kapkac, Murat; Girgin, Sadullah; Tireli, Mustafa; Ihtiyar, Enver; Demircan, Orhan; Baskan, Mazhar Semih; Koyuncu, Ayhan; Tasdelen, Ismet; Dumanli, Esra; Ozdener, Fatih; Zaborek, Piotr

2015-01-01

Background: One of the most important factors in breast cancer (BC) mortality is treatment delay. The primary goal of this survey was to identify factors affecting the total delay time (TDT) in Turkish BC patients. Methods: A total of 1031 patients with BC were surveyed using a uniform questionnaire. The time between discovering the first symptom and signing up for the first medical visit (patient delay time; PDT) and the time between the first medical visit and the start of therapy (system delay time; SDT) were modelled separately with multilevel regression. Results: The mean PDT, SDT and TDT were 4.8, 10.5 and 13.8 weeks, respectively. In all, 42% of the patients had a TDT >12 weeks. Longer PDT was significantly correlated with disregarding symptoms and having age of between 30 and 39 years. Shorter PDT was characteristic of patients who: had stronger self-examination habits, received more support from family and friends and had at least secondary education. Predictors of longer SDT included disregard of symptoms, distrust in success of therapy and medical system and having PDT in excess of 4 weeks. Shorter SDT was linked to the age of >60 years. Patients who were diagnosed during a periodic check-up or opportunistic mammography displayed shorter SDT compared with those who had symptomatic BC and their first medical examination was by a surgeon. Conclusion: TDT in Turkey is long and remains a major problem. Delays can be reduced by increasing BC awareness, implementing organized population-based screening programmes and founding cancer centres. PMID:25096257

About Distributed Simulation-based Optimization of Forming Processes using a Grid Architecture

NASA Astrophysics Data System (ADS)

Grauer, Manfred; Barth, Thomas

2004-06-01

Permanently increasing complexity of products and their manufacturing processes combined with a shorter "time-to-market" leads to more and more use of simulation and optimization software systems for product design. Finding a "good" design of a product implies the solution of computationally expensive optimization problems based on the results of simulation. Due to the computational load caused by the solution of these problems, the requirements on the Information&Telecommunication (IT) infrastructure of an enterprise or research facility are shifting from stand-alone resources towards the integration of software and hardware resources in a distributed environment for high-performance computing. Resources can either comprise software systems, hardware systems, or communication networks. An appropriate IT-infrastructure must provide the means to integrate all these resources and enable their use even across a network to cope with requirements from geographically distributed scenarios, e.g. in computational engineering and/or collaborative engineering. Integrating expert's knowledge into the optimization process is inevitable in order to reduce the complexity caused by the number of design variables and the high dimensionality of the design space. Hence, utilization of knowledge-based systems must be supported by providing data management facilities as a basis for knowledge extraction from product data. In this paper, the focus is put on a distributed problem solving environment (PSE) capable of providing access to a variety of necessary resources and services. A distributed approach integrating simulation and optimization on a network of workstations and cluster systems is presented. For geometry generation the CAD-system CATIA is used which is coupled with the FEM-simulation system INDEED for simulation of sheet-metal forming processes and the problem solving environment OpTiX for distributed optimization.

An Accurate and Efficient Algorithm for Detection of Radio Bursts with an Unknown Dispersion Measure, for Single-dish Telescopes and Interferometers

NASA Astrophysics Data System (ADS)

Zackay, Barak; Ofek, Eran O.

2017-01-01

Astronomical radio signals are subjected to phase dispersion while traveling through the interstellar medium. To optimally detect a short-duration signal within a frequency band, we have to precisely compensate for the unknown pulse dispersion, which is a computationally demanding task. We present the “fast dispersion measure transform” algorithm for optimal detection of such signals. Our algorithm has a low theoretical complexity of 2{N}f{N}t+{N}t{N}{{Δ }}{{log}}2({N}f), where Nf, Nt, and NΔ are the numbers of frequency bins, time bins, and dispersion measure bins, respectively. Unlike previously suggested fast algorithms, our algorithm conserves the sensitivity of brute-force dedispersion. Our tests indicate that this algorithm, running on a standard desktop computer and implemented in a high-level programming language, is already faster than the state-of-the-art dedispersion codes running on graphical processing units (GPUs). We also present a variant of the algorithm that can be efficiently implemented on GPUs. The latter algorithm’s computation and data-transport requirements are similar to those of a two-dimensional fast Fourier transform, indicating that incoherent dedispersion can now be considered a nonissue while planning future surveys. We further present a fast algorithm for sensitive detection of pulses shorter than the dispersive smearing limits of incoherent dedispersion. In typical cases, this algorithm is orders of magnitude faster than enumerating dispersion measures and coherently dedispersing by convolution. We analyze the computational complexity of pulsed signal searches by radio interferometers. We conclude that, using our suggested algorithms, maximally sensitive blind searches for dispersed pulses are feasible using existing facilities. We provide an implementation of these algorithms in Python and MATLAB.

Determinants of Return to Play After the Nonoperative Management of Hamstring Injuries in Athletes: A Systematic Review.

PubMed

Fournier-Farley, Camille; Lamontagne, Martin; Gendron, Patrick; Gagnon, Dany H

2016-08-01

It is important for clinicians to rely on suitable prognosis factors after hamstring injuries because of the high incidence of these injuries and time away from athletic activities. To summarize the current literature on factors that influence return to play after a hamstring injury in athletes. Systematic review. A computer-assisted literature search of CINAHL, MEDLINE, Embase, and EBM Reviews databases (and a manual search of the reference lists of all selected articles) was conducted using keywords related to hamstring injuries and return to play. The literature review criteria included (1) patients with an acute hamstring or posterior thigh injury; (2) a randomized controlled trial, cohort study, case-control study, case series, or prospective or retrospective design; (3) information on rehabilitation, physical therapy, clinical assessment, imaging techniques, and return to play; and (4) studies written in English or French. The search strategy identified 914 potential articles, of which 24 met the inclusion criteria. In terms of the clinical assessment, the following factors were associated with a longer recovery time: stretching-type injuries, recreational-level sports, structural versus functional injuries, greater range of motion deficit with the hip flexed at 90°, time to first consultation >1 week, increased pain on the visual analog scale, and >1 day to be able to walk pain free after the injury. As for magnetic resonance imaging studies, the following factors correlated with a longer recovery time: positive findings; higher grade of injury; muscle involvement >75%; complete transection; retraction; central tendon disruption of the biceps femoris; proximal tendon involvement; shorter distance to the ischial tuberosity; length of the hamstring injury; and depth, volume, and large cross-sectional area. With respect to ultrasound studies, the following factors were associated with a poor prognosis: large cross-sectional area, injury outside the musculotendinous junction, hematoma, structural injury, and injury involving the biceps femoris. Lastly, rehabilitation approaches that included hamstring loading during extensive lengthening or 4 daily sessions of static hamstring stretching led to shorter rehabilitation times. Numerous determinants have an effect on return to play after a hamstring injury in athletes. It is important for sports professionals to be aware of those determinants to guide athletes through the rehabilitation process and refine return-to-play strategies. © 2015 The Author(s).

Meeting national response time targets for priority 1 incidents in an urban emergency medical services system in South Africa: More ambulances won't help.

PubMed

Stein, Christopher; Wallis, Lee; Adetunji, Olufemi

2015-09-19

Response time is viewed as a key performance indicator in most emergency medical services (EMS) systems. To determine the effect of increased emergency vehicle numbers on response time performance for priority 1 incidents in an urban EMS system in Cape Town, South Africa, using discrete-event computer simulation. A simulation model was created, based on input data from part of the EMS operations. Two different versions of the model were used, one with primary response vehicles and ambulances and one with only ambulances. In both cases the models were run in seven different scenarios. The first scenario used the actual number of emergency vehicles in the real system, and in each subsequent scenario vehicle numbers were increased by adding the baseline number to the cumulative total. The model using only ambulances had shorter response times and a greater number of responses meeting national response time targets than models using primary response vehicles and ambulances. In both cases an improvement in response times and the number of responses meeting national response time targets was observed with the first incremental addition of vehicles. After this the improvements rapidly diminished and eventually became negligible with each successive increase in vehicle numbers. The national response time target for urban areas was never met, even with a seven-fold increase in vehicle numbers. The addition of emergency vehicles to an urban EMS system improves response times in priority 1 incidents, but alone is not capable of the magnitude of response time improvement needed to meet the national response time targets.

Subseasonal prediction of the heat wave of December 2013 in Southern South America by the POAMA and BCC-CPS models

NASA Astrophysics Data System (ADS)

Osman, Marisol; Alvarez, Mariano S.

2018-01-01

The prediction skill of subseasonal forecast models is evaluated for a strong and long-lasting heat wave occurred in December 2013 over Southern South America. Reforecasts from two models participating in the WCRP/WWRP Subseasonal to Seasonal project, the Bureau of Meteorology POAMA and Beijing Climate Center model BCC-CPS were considered to evaluate their skill in forecasting temperature and circulation anomalies during that event. The POAMA reforecast of 32-member ensemble size, initialized every five days, and BCC-CPS reforecast of 4-member ensemble size for the same date of POAMA plus the previous 4 days were considered. Weekly ensemble-mean forecasts were computed with leadtimes from 2 days up to 24 days every 5 days. Weekly anomalies were calculated for observations from 13th of December to 31st of December 2013. Anomalies for both observations and reforecast were calculated with respect to their own climatology. Results show that the ensemble mean warm anomalies forecasted for week 1 and 2 of the heat wave resulted more similar to the observations for the POAMA model, especially for longer leads. The BCC-CPS performed better for leads shorter than 7 (14) for week 1 (2). For week 3 the BCC-CPS outperformed the POAMA model, particularly at shorter leads, locating more accurately the maxima of the anomalies. In a probabilistic approach, POAMA predicted with a higher chance than BCC-CPS the excess of the upper tercile of temperature anomalies for almost every week and lead time. The forecast of the circulation anomalies over South America could be used to explain the location of the highest temperature anomalies. In summary, for this case, models skill in forecasting surface temperature in a context of a heat wave resulted moderate at lead times longer than the fortnight. However, this study is limited to model-to-model analysis and a multi-model ensemble strategy might increase the skill.

Delay Within the 3-Hour Surviving Sepsis Campaign Guideline on Mortality for Patients With Severe Sepsis and Septic Shock.

PubMed

Pruinelli, Lisiane; Westra, Bonnie L; Yadav, Pranjul; Hoff, Alexander; Steinbach, Michael; Kumar, Vipin; Delaney, Connie W; Simon, Gyorgy

2018-04-01

To specify when delays of specific 3-hour bundle Surviving Sepsis Campaign guideline recommendations applied to severe sepsis or septic shock become harmful and impact mortality. Retrospective cohort study. One health system composed of six hospitals and 45 clinics in a Midwest state from January 01, 2011, to July 31, 2015. All adult patients hospitalized with billing diagnosis of severe sepsis or septic shock. Four 3-hour Surviving Sepsis Campaign guideline recommendations: 1) obtain blood culture before antibiotics, 2) obtain lactate level, 3) administer broad-spectrum antibiotics, and 4) administer 30 mL/kg of crystalloid fluid for hypotension (defined as "mean arterial pressure" < 65) or lactate (> 4). To determine the effect of t minutes of delay in carrying out each intervention, propensity score matching of "baseline" characteristics compensated for differences in health status. The average treatment effect in the treated computed as the average difference in outcomes between those treated after shorter versus longer delay. To estimate the uncertainty associated with the average treatment effect in the treated metric and to construct 95% CIs, bootstrap estimation with 1,000 replications was performed. From 5,072 patients with severe sepsis or septic shock, 1,412 (27.8%) had in-hospital mortality. The majority of patients had the four 3-hour bundle recommendations initiated within 3 hours. The statistically significant time in minutes after which a delay increased the risk of death for each recommendation was as follows: lactate, 20.0 minutes; blood culture, 50.0 minutes; crystalloids, 100.0 minutes; and antibiotic therapy, 125.0 minutes. The guideline recommendations showed that shorter delays indicates better outcomes. There was no evidence that 3 hours is safe; even very short delays adversely impact outcomes. Findings demonstrated a new approach to incorporate time t when analyzing the impact on outcomes and provide new evidence for clinical practice and research.

Ensembles of adaptive spatial filters increase BCI performance: an online evaluation

NASA Astrophysics Data System (ADS)

Sannelli, Claudia; Vidaurre, Carmen; Müller, Klaus-Robert; Blankertz, Benjamin

2016-08-01

Objective: In electroencephalographic (EEG) data, signals from distinct sources within the brain are widely spread by volume conduction and superimposed such that sensors receive mixtures of a multitude of signals. This reduction of spatial information strongly hampers single-trial analysis of EEG data as, for example, required for brain-computer interfacing (BCI) when using features from spontaneous brain rhythms. Spatial filtering techniques are therefore greatly needed to extract meaningful information from EEG. Our goal is to show, in online operation, that common spatial pattern patches (CSPP) are valuable to counteract this problem. Approach: Even though the effect of spatial mixing can be encountered by spatial filters, there is a trade-off between performance and the requirement of calibration data. Laplacian derivations do not require calibration data at all, but their performance for single-trial classification is limited. Conversely, data-driven spatial filters, such as common spatial patterns (CSP), can lead to highly distinctive features; however they require a considerable amount of training data. Recently, we showed in an offline analysis that CSPP can establish a valuable compromise. In this paper, we confirm these results in an online BCI study. In order to demonstrate the paramount feature that CSPP requires little training data, we used them in an adaptive setting with 20 participants and focused on users who did not have success with previous BCI approaches. Main results: The results of the study show that CSPP adapts faster and thereby allows users to achieve better feedback within a shorter time than previous approaches performed with Laplacian derivations and CSP filters. The success of the experiment highlights that CSPP has the potential to further reduce BCI inefficiency. Significance: CSPP are a valuable compromise between CSP and Laplacian filters. They allow users to attain better feedback within a shorter time and thus reduce BCI inefficiency to one-fourth in comparison to previous non-adaptive paradigms.

Ensembles of adaptive spatial filters increase BCI performance: an online evaluation.

PubMed

Sannelli, Claudia; Vidaurre, Carmen; Müller, Klaus-Robert; Blankertz, Benjamin

2016-08-01

In electroencephalographic (EEG) data, signals from distinct sources within the brain are widely spread by volume conduction and superimposed such that sensors receive mixtures of a multitude of signals. This reduction of spatial information strongly hampers single-trial analysis of EEG data as, for example, required for brain-computer interfacing (BCI) when using features from spontaneous brain rhythms. Spatial filtering techniques are therefore greatly needed to extract meaningful information from EEG. Our goal is to show, in online operation, that common spatial pattern patches (CSPP) are valuable to counteract this problem. Even though the effect of spatial mixing can be encountered by spatial filters, there is a trade-off between performance and the requirement of calibration data. Laplacian derivations do not require calibration data at all, but their performance for single-trial classification is limited. Conversely, data-driven spatial filters, such as common spatial patterns (CSP), can lead to highly distinctive features; however they require a considerable amount of training data. Recently, we showed in an offline analysis that CSPP can establish a valuable compromise. In this paper, we confirm these results in an online BCI study. In order to demonstrate the paramount feature that CSPP requires little training data, we used them in an adaptive setting with 20 participants and focused on users who did not have success with previous BCI approaches. The results of the study show that CSPP adapts faster and thereby allows users to achieve better feedback within a shorter time than previous approaches performed with Laplacian derivations and CSP filters. The success of the experiment highlights that CSPP has the potential to further reduce BCI inefficiency. CSPP are a valuable compromise between CSP and Laplacian filters. They allow users to attain better feedback within a shorter time and thus reduce BCI inefficiency to one-fourth in comparison to previous non-adaptive paradigms.

Evidence based medicine and surgical approaches for colon cancer: evidences, benefits and limitations of the laparoscopic vs open resection.

PubMed

Lorenzon, Laura; La Torre, Marco; Ziparo, Vincenzo; Montebelli, Francesco; Mercantini, Paolo; Balducci, Genoveffa; Ferri, Mario

2014-04-07

To report a meta-analysis of the studies that compared the laparoscopic with the open approach for colon cancer resection. Forty-seven manuscripts were reviewed, 33 of which employed for meta-analysis according to the PRISMA guidelines. The results were differentiated according to the study design (prospective randomized trials vs case-control series) and according to the tumor's location. Outcome measures included: (1) short-term results (operating times, blood losses, bowel function recovery, post-operative pain, return to the oral intake, complications and hospital stay); (2) oncological adequateness (number of nodes harvested in the surgical specimens); and (3) long-term results (including the survivals' rates and incidence of incisional hernias) and (4) costs. Meta-analysis of trials provided evidences in support of the laparoscopic procedures for a several short-term outcomes including: a lower blood loss, an earlier recovery of the bowel function, an earlier return to the oral intake, a shorter hospital stay and a lower morbidity rate. Opposite the operating time has been confirmed shorter in open surgery. The same trend has been reported investigating case-control series and cancer by sites, even though there are some concerns regarding the power of the studies in this latter field due to the small number of trials and the small sample of patients enrolled. The two approaches were comparable regarding the mean number of nodes harvested and long-term results, even though these variables were documented reviewing the literature but were not computable for meta-analysis. The analysis of the costs documented lower costs for the open surgery, however just few studies investigated the incidence of post-operative hernias. Laparoscopy is superior for the majority of short-term results. Future studies should better differentiate these approaches on the basis of tumors' location and the post-operative hernias.

Free-Space Quantum Signatures Using Heterodyne Measurements

NASA Astrophysics Data System (ADS)

Croal, Callum; Peuntinger, Christian; Heim, Bettina; Khan, Imran; Marquardt, Christoph; Leuchs, Gerd; Wallden, Petros; Andersson, Erika; Korolkova, Natalia

2016-09-01

Digital signatures guarantee the authorship of electronic communications. Currently used "classical" signature schemes rely on unproven computational assumptions for security, while quantum signatures rely only on the laws of quantum mechanics to sign a classical message. Previous quantum signature schemes have used unambiguous quantum measurements. Such measurements, however, sometimes give no result, reducing the efficiency of the protocol. Here, we instead use heterodyne detection, which always gives a result, although there is always some uncertainty. We experimentally demonstrate feasibility in a real environment by distributing signature states through a noisy 1.6 km free-space channel. Our results show that continuous-variable heterodyne detection improves the signature rate for this type of scheme and therefore represents an interesting direction in the search for practical quantum signature schemes. For transmission values ranging from 100% to 10%, but otherwise assuming an ideal implementation with no other imperfections, the signature length is shorter by a factor of 2 to 10. As compared with previous relevant experimental realizations, the signature length in this implementation is several orders of magnitude shorter.

Propofol for procedural sedation and analgesia reduced dedicated emergency nursing time while maintaining safety in a community emergency department.

PubMed

Reynolds, Joshua C; Abraham, Michael K; Barrueto, Fermin F; Lemkin, Daniel L; Hirshon, Jon M

2013-09-01

Procedural sedation and analgesia is a core competency in emergency medicine. Propofol is replacing midazolam in many emergency departments. Barriers to performing procedural sedation include resource utilization. We hypothesized that emergency nursing time is shorter with propofol than midazolam, without increasing complications. Retrospective analysis of a procedural sedation registry for two community emergency departments with combined census of 100,000 patients/year. Demographics, procedure, and ASA physical classification status of adult patients receiving procedural sedation between 2007-2010 with midazolam or propofol were analyzed. Primary outcome was dedicated emergency nursing time. Secondary outcomes were procedural success, ED length of stay, and complication rate. Comparative statistics were performed with Mann-Whitney, Kruskal-Wallis, chi-square, or Fisher's exact test. Linear regression was performed with log-transformed procedural sedation time to define predictors. Of 328 procedural sedation and analgesia, 316 met inclusion criteria, of which 60 received midazolam and 256 propofol. Sex distribution varied between groups (midazolam 3% male; propofol 55% male; P = 0.04). Age, procedure, and ASA status were not significantly different. Propofol had shorter procedural sedation time (propofol 32.5 ± 24.2 minutes; midazolam 78.7 ± 51.5 minutes; P < 0.001) and higher rates of procedural success (propofol 98%; midazolam 92%; P = 0.02). There were no significant differences between complication rates (propofol 14%; midazolam 13%; P = 0.88) or emergency department length of stay (propofol 262.5 ± 132.8 minutes; midazolam 288.6 ± 130.6 minutes; P = 0.09). Use of propofol resulted in shorter emergency nursing time and higher procedural success rate than midazolam with a comparable safety profile. Copyright © 2013 Emergency Nurses Association. Published by Mosby, Inc. All rights reserved.

Electroacupuncture reduces duration of postoperative ileus after laparoscopic surgery for colorectal cancer.

PubMed

Ng, Simon S M; Leung, Wing Wa; Mak, Tony W C; Hon, Sophie S F; Li, Jimmy C M; Wong, Cherry Y N; Tsoi, Kelvin K F; Lee, Janet F Y

2013-02-01

We investigated the efficacy of electroacupuncture in reducing the duration of postoperative ileus and hospital stay after laparoscopic surgery for colorectal cancer. We performed a prospective study of 165 patients undergoing elective laparoscopic surgery for colonic and upper rectal cancer, enrolled from October 2008 to October 2010. Patients were assigned randomly to groups that received electroacupuncture (n = 55) or sham acupuncture (n = 55), once daily from postoperative days 1-4, or no acupuncture (n = 55). The acupoints Zusanli, Sanyinjiao, Hegu, and Zhigou were used. The primary outcome was time to defecation. Secondary outcomes included postoperative analgesic requirement, time to ambulation, and length of hospital stay. Patients who received electroacupuncture had a shorter time to defecation than patients who received no acupuncture (85.9 ± 36.1 vs 122.1 ± 53.5 h; P < .001) and length of hospital stay (6.5 ± 2.2 vs 8.5 ± 4.8 days; P = .007). Patients who received electroacupuncture also had a shorter time to defecation than patients who received sham acupuncture (85.9 ± 36.1 vs 107.5 ± 46.2 h; P = .007). Electroacupuncture was more effective than no or sham acupuncture in reducing postoperative analgesic requirement and time to ambulation. In multiple linear regression analysis, an absence of complications and electroacupuncture were associated with a shorter duration of postoperative ileus and hospital stay after the surgery. In a clinical trial, electroacupuncture reduced the duration of postoperative ileus, time to ambulation, and postoperative analgesic requirement, compared with no or sham acupuncture, after laparoscopic surgery for colorectal cancer. ClinicalTrials.gov number, NCT00464425. Copyright © 2013 AGA Institute. Published by Elsevier Inc. All rights reserved.

The timing of exposure in clinic-based treatment for childhood anxiety disorders.

PubMed

Gryczkowski, Michelle R; Tiede, Michael S; Dammann, Julie E; Jacobsen, Amy Brown; Hale, Lisa R; Whiteside, Stephen P H

2013-03-01

The present study examines treatment length and timing of exposure from two child anxiety disorders clinics. Data regarding symptoms and treatment characteristics for 28 youth were prospectively obtained through self, parent, and therapist report at each session. Information regarding length of treatment, timing of exposure initiation, and drop-out rates were compared with those obtained through efficacy and effectiveness trials of manualized treatment for anxious youth. Findings from the authors' clinical data revealed significantly shorter treatment duration with exposures implemented sooner than in the previous studies. Dropout rates were significantly higher than in the efficacy trial but comparable with the effectiveness trial. Outcome data from a subset of eight patients revealed large effect sizes. These findings suggest that effective treatment can be shorter and more focused on exposure than is often outlined in manuals and have important implications for outcome research and dissemination.

Planetary camera observations of the central parsec of M32

NASA Technical Reports Server (NTRS)

Lauer, Tod R.; Faber, S. M.; Currie, Douglas G.; Ewald, S. P.; Groth, Edward J.; Hester, J. J.; Holtzman, Jon A.; Light, Robert M.; O'Neil, Earl J., Jr.; Shaya, Edward J.

1992-01-01

New HST observations are reported which show that the M32 nucleus is extremely dense, with rho0 not less than 4 x 10 exp 6 solar masses/cu pc if M32 has a core with rc not greater than 0.37 pc, and rho0 greater than 3 x 10 exp 7 solar masses/cu pc if it instead has a central r exp -1/2 cusp. Limits on the M32 core radius are nearly three times smaller, and those on the central density at least four times greater, than values inferred from the best ground-based observations. A central relaxation that is almost an order of magnitude shorter than previous estimates is inferred from the new core parameters; a shorter stellar collision time is also inferred. It is argued that a starlight cusp surrounds the central black hole.

Planetary camera observations of the central parsec of M32

NASA Astrophysics Data System (ADS)

Lauer, Tod R.; Faber, S. M.; Currie, Douglas G.; Ewald, S. P.; Groth, Edward J.; Hester, J. Jeff; Holtzman, Jon A.; Light, Robert M.; O'Neil, Earl J., Jr.; Shaya, Edward J.; Westphal, James A.

1992-08-01

New HST observations are reported which show that the M32 nucleus is extremely dense, with rho0 not less than 4 x 10 exp 6 solar masses/cu pc if M32 has a core with rc not greater than 0.37 pc, and rho0 greater than 3 x 10 exp 7 solar masses/cu pc if it instead has a central r exp -1/2 cusp. Limits on the M32 core radius are nearly three times smaller, and those on the central density at least four times greater, than values inferred from the best ground-based observations. A central relaxation that is almost an order of magnitude shorter than previous estimates is inferred from the new core parameters; a shorter stellar collision time is also inferred. It is argued that a starlight cusp surrounds the central black hole.

Battery Lifespan | Transportation Research | NREL

Science.gov Websites

over time (ranging from 0 to 15 years) for three different climates (represented by Minneapolis . Trend lines from upper left to lower right reflect diminished capacity over time and shorter lifespan in Battery Life Model. Graph of relative capacity (ranging from .75 to 1) of battery in percent over time

Effects of processing parameters on immersion vacuum cooling time and physico-chemical properties of pork hams.

PubMed

Feng, Chao-Hui; Drummond, Liana; Zhang, Zhi-Hang; Sun, Da-Wen

2013-10-01

The effects of agitation (1002 rpm), different pressure reduction rates (60 and 100 mbar/min), as well as employing cold water with different initial temperatures (IWT: 7 and 20°C) on immersion vacuum cooling (IVC) of cooked pork hams were experimentally investigated. Final pork ham core temperature, cooling time, cooling loss, texture properties, colour and chemical composition were evaluated. The application for the first time of agitation during IVC substantially reduced the cooling time (47.39%) to 4.6°C, compared to IVC without agitation. For the different pressure drop rates, there was a trend that shorter IVC cooling times were achieved with lower cooling rate, although results were not statistically significant (P>0.05). For both IWTs tested, the same trend was observed: shorter cooling time and lower cooling loss were obtained under lower linear pressure drop rate of 60 mbar/min (not statistically significant, P>0.05). Compared to the reference cooling method (air blast cooling), IVC achieved higher cooling rates and better meat quality. Copyright © 2013 Elsevier Ltd. All rights reserved.

Motion illusions in optical art presented for long durations are temporally distorted.

PubMed

Nather, Francisco Carlos; Mecca, Fernando Figueiredo; Bueno, José Lino Oliveira

2013-01-01

Static figurative images implying human body movements observed for shorter and longer durations affect the perception of time. This study examined whether images of static geometric shapes would affect the perception of time. Undergraduate participants observed two Optical Art paintings by Bridget Riley for 9 or 36 s (group G9 and G36, respectively). Paintings implying different intensities of movement (2.0 and 6.0 point stimuli) were randomly presented. The prospective paradigm in the reproduction method was used to record time estimations. Data analysis did not show time distortions in the G9 group. In the G36 group the paintings were differently perceived: that for the 2.0 point one are estimated to be shorter than that for the 6.0 point one. Also for G36, the 2.0 point painting was underestimated in comparison with the actual time of exposure. Motion illusions in static images affected time estimation according to the attention given to the complexity of movement by the observer, probably leading to changes in the storage velocity of internal clock pulses.

Thermal inactivation of Listeria innocua in salmon (Oncorhynchus keta) caviar using conventional glass and novel aluminum thermal-death-time tubes.

PubMed

Al-Holy, M; Quinde, Z; Guan, D; Tang, J; Rasco, B

2004-02-01

Differences in the come-up times and thermal inactivation parameters of Listeria innocua in salmon (Oncorhynchus keta) caviar containing 2.5% salt using conventional thermal-death-time (TDT) glass tubes and a novel aluminum tube were tested and compared. Generally, the come-up times and decimal reduction times (D-values) were shorter and the change in temperature required to change the D-value (z-value) was longer in the aluminum than in the glass tubes. The D-values at 60, 63, and 65 degrees C for the aluminum TDT tubes were 2.97, 0.77, and 0.40 min, respectively, and for the glass TDT tubes, these values were 3.55, 0.84, and 0.41 min. The z-values were 5.7 degrees C in the aluminum and 5.3 degrees C in the glass. Because of the shorter come-up time, the aluminum TDT tubes may provide a more precise measurement of microbial thermal inactivation than the glass TDT tubes, particularly for viscous materials, solid foods, and foods containing particulate matter.

Probabilistic density function method for nonlinear dynamical systems driven by colored noise.

PubMed

Barajas-Solano, David A; Tartakovsky, Alexandre M

2016-05-01

We present a probability density function (PDF) method for a system of nonlinear stochastic ordinary differential equations driven by colored noise. The method provides an integrodifferential equation for the temporal evolution of the joint PDF of the system's state, which we close by means of a modified large-eddy-diffusivity (LED) closure. In contrast to the classical LED closure, the proposed closure accounts for advective transport of the PDF in the approximate temporal deconvolution of the integrodifferential equation. In addition, we introduce the generalized local linearization approximation for deriving a computable PDF equation in the form of a second-order partial differential equation. We demonstrate that the proposed closure and localization accurately describe the dynamics of the PDF in phase space for systems driven by noise with arbitrary autocorrelation time. We apply the proposed PDF method to analyze a set of Kramers equations driven by exponentially autocorrelated Gaussian colored noise to study nonlinear oscillators and the dynamics and stability of a power grid. Numerical experiments show the PDF method is accurate when the noise autocorrelation time is either much shorter or longer than the system's relaxation time, while the accuracy decreases as the ratio of the two timescales approaches unity. Similarly, the PDF method accuracy decreases with increasing standard deviation of the noise.

Optimizing Aircraft Trajectories with Multiple Cruise Altitudes in the Presence of Winds

NASA Technical Reports Server (NTRS)

Ng, Hok K.; Sridhar, Banavar; Grabbe, Shon

2014-01-01

This study develops a trajectory optimization algorithm for approximately minimizing aircraft travel time and fuel burn by combining a method for computing minimum-time routes in winds on multiple horizontal planes, and an aircraft fuel burn model for generating fuel-optimal vertical profiles. It is applied to assess the potential benefits of flying user-preferred routes for commercial cargo flights operating between Anchorage, Alaska and major airports in Asia and the contiguous United States. Flying wind optimal trajectories with a fuel-optimal vertical profile reduces average fuel burn of international flights cruising at a single altitude by 1-3 percent. The potential fuel savings of performing en-route step climbs are not significant for many shorter domestic cargo flights that have only one step climb. Wind-optimal trajectories reduce fuel burn and travel time relative to the flight plan route by up to 3 percent for the domestic cargo flights. However, for trans-oceanic traffic, the fuel burn savings could be as much as 10 percent. The actual savings in operations will vary from the simulation results due to differences in the aircraft models and user defined cost indices. In general, the savings are proportional to trip length, and depend on the en-route wind conditions and aircraft types.

Group-V atoms exchange due to exposure of InP surface to AsH3(+PH3) revealed by x-ray CTR scattering

NASA Astrophysics Data System (ADS)

Tabuchi, M.; Yamada, N.; Fujibayashi, K.; Takeda, Y.; Kamei, H.

1996-05-01

We conducted x-ray crystal truncation rod (CTR) measurements using synchro-tron radiation to analyze the As atom distribution in InP to the order of 1 ML. The InP samples which were only exposed to AsH3(+PH3) and capped by InP were investigated to study the effect of the purge sequence. The purge sequence is unavoidable to grow heteroepitaxial layers by OMVPE and is considered to affect largely the structure of the interface. From the results of the measurement and the computer simulation, the distribution of P and As atoms of the order of 1 ML was discussed as functions of the exposing time. It was shown that the number of As atoms contained in the samples saturated when the AsH3-exposure time is longer than 10 s. Comparing the profiles of AsH3-exposed samples with that of (AsH3 + PH3)-exposed samples, it was found that the As distribution in the buffer layer was suppressed in (AsH3 + PH3)-exposed samples. In order to obtain the sharp interfaces, the AsH3-exposure time must be shorter than 0.5 s.

[A study of the phenomenon of voice intonation: analysis, usage and diagnosis].

PubMed

Kazanecka, E; Pawłowski, Z; Zółtowski, M

1997-01-01

The aim of this work was to study the average rise time (RT) and average flow rate (MRT) in utterance. Data were collected from 48 singers and 44 patients. The group of patients included cases of modulus vocale, polypus laryngis, paresis bilateralis, hemiparesis, and CA laryngis. Various characteristics of utterance were recorded synchronously: the frequency and intensity of the fundamental laryngeal tone were measured with a laryngophone, a microphone was used to monitor acoustic radiation from the mouth, and a pneumotrachometer was applied for the measurement of flow rate. The data were stored and analysed with the use of a computer. Results show that the analysis carried out in the study describes the distinctive characteristics of normal and pathologic utterance. The main findings are as follows: a) rise time (RT) decreases with increasing loudness and pitch of the sound and is also shorter in staccato than inlegato sounds; b) during the initial transient of staccato sounds, the average flow rate in the glottis increases with intensity and pitch of the sound; c) pre-fonation time (TPP) and air volume do not differentiate normal and pathologic utterance; d) in cases of voice pathology, the analysis of utterance described in this study can be used for the evaluation of therapy and rehabilitation.

On the estimation of brain signal entropy from sparse neuroimaging data

PubMed Central

Grandy, Thomas H.; Garrett, Douglas D.; Schmiedek, Florian; Werkle-Bergner, Markus

2016-01-01

Multi-scale entropy (MSE) has been recently established as a promising tool for the analysis of the moment-to-moment variability of neural signals. Appealingly, MSE provides a measure of the predictability of neural operations across the multiple time scales on which the brain operates. An important limitation in the application of the MSE to some classes of neural signals is MSE’s apparent reliance on long time series. However, this sparse-data limitation in MSE computation could potentially be overcome via MSE estimation across shorter time series that are not necessarily acquired continuously (e.g., in fMRI block-designs). In the present study, using simulated, EEG, and fMRI data, we examined the dependence of the accuracy and precision of MSE estimates on the number of data points per segment and the total number of data segments. As hypothesized, MSE estimation across discontinuous segments was comparably accurate and precise, despite segment length. A key advance of our approach is that it allows the calculation of MSE scales not previously accessible from the native segment lengths. Consequently, our results may permit a far broader range of applications of MSE when gauging moment-to-moment dynamics in sparse and/or discontinuous neurophysiological data typical of many modern cognitive neuroscience study designs. PMID:27020961

Measurement of duration and signal-to-noise ratio of astronomical transients using a Spectral Kurtosis spectrometer

NASA Astrophysics Data System (ADS)

Nita, Gelu M.; Gary, Dale E.

2016-08-01

Following our prior theoretical and instrumental work addressing the problem of automatic real-time radio frequency interference (RFI) detection and excision from astronomical signals, the wideband Spectral Kurtosis (SK) spectrometer design we proposed is currently being considered as an alternative to the traditional spectrometers when building the new generation of radio instruments. The unique characteristic of an SK spectrometer is that it accumulates both power and power-squared, which are then used to compute an SK statistical estimator proven to be very effective in detecting and excising certain types of RFI signals. In this paper we introduce a novel measurement technique that exploits the power and power square statistics of an SK spectrometer to determine durations and signal-to-noise ratios of transient signals, whether they are RFI or natural signals, even when they are below the time resolution of the instrument. We demonstrate this novel experimental technique by analyzing a segment of data recorded by the Expanded Owens Valley Solar Array Subsystem Testbed (EST) during a solar radio burst in which microwave spike bursts occurred with durations shorter than the 20 ms time resolution of the instrument. The duration of one well-observed spike is quantitatively shown to be within a few percent of 8 ms despite the 20 ms resolution of the data.

Treatment of malignant gastric outlet obstruction with endoscopically placed self-expandable metal stents

PubMed Central

Gaidos, Jill KJ; Draganov, Peter V

2009-01-01

Malignant gastroduodenal obstruction can occur in up to 20% of patients with primary pancreatic, gastric or duodenal carcinomas. Presenting symptoms include nausea, vomiting, abdominal distention, pain and decreased oral intake which can lead to dehydration, malnutrition, and poor quality of life. Endoscopic stent placement has become the primary therapeutic modality because it is safe, minimally invasive, and a cost-effective option for palliation. Stents can be successfully deployed in the majority of patients. Stent placement appears to lead to a shorter time to symptomatic improvement, shorter time to resumption of an oral diet, and shorter hospital stays as compared with surgical options. Recurrence of the obstructive symptoms resulting from stent occlusion, due to tumor ingrowth or overgrowth, can be successfully treated with repeat endoscopic stent placement in the majority of the cases. Both endoscopic stenting and surgical bypass are considered palliative treatments and, to date, no improvement in survival with either modality has been demonstrated. A tailored therapeutic approach, taking into consideration patient preferences and involving a multidisciplinary team including the therapeutic endoscopist, surgeon, medical oncologist, radiation therapist, and interventional radiologist, should be considered in all cases. PMID:19764086

High-Frequency Switching Transients and Power Loss Estimation in Electric Drive Systems that Utilize Wide-Bandgap Semiconductors

NASA Astrophysics Data System (ADS)

Fulani, Olatunji T.

Development of electric drive systems for transportation and industrial applications is rapidly seeing the use of wide-bandgap (WBG) based power semiconductor devices. These devices, such as SiC MOSFETs, enable high switching frequencies and are becoming the preferred choice in inverters because of their lower switching losses and higher allowable operating temperatures. Due to the much shorter turn-on and turn-off times and correspondingly larger output voltage edge rates, traditional models and methods previously used to estimate inverter and motor power losses, based upon a triangular power loss waveform, are no longer justifiable from a physical perspective. In this thesis, more appropriate models and a power loss calculation approach are described with the goal of more accurately estimating the power losses in WBG-based electric drive systems. Sine-triangle modulation with third harmonic injection is used to control the switching of the inverter. The motor and inverter models are implemented using Simulink and computer studies are shown illustrating the application of the new approach.

Remote Sensing Application to Land Use Classification in a Rapidly Changing Agricultural/Urban Area: City of Virginia Beach, Virginia. Ph.D. Thesis

NASA Technical Reports Server (NTRS)

Odenyo, V. A. O.

1975-01-01

Remote sensing data on computer-compatible tapes of LANDSAT 1 multispectral scanner imager were analyzed to generate a land use map of the City of Virginia Beach. All four bands were used in both the supervised and unsupervised approaches with the LAYSYS software system. Color IR imagery of a U-2 flight of the same area was also digitized and two sample areas were analyzed via the unsupervised approach. The relationships between the mapped land use and the soils of the area were investigated. A land use land cover map at a scale of 1:24,000 was obtained from the supervised analysis of LANDSAT 1 data. It was concluded that machine analysis of remote sensing data to produce land use maps was feasible; that the LAYSYS software system was usable for this purpose; and that the machine analysis was capable of extracting detailed information from the relatively small scale LANDSAT data in a much shorter time without compromising accuracy.

A multi-objective genetic algorithm for a mixed-model assembly U-line balancing type-I problem considering human-related issues, training, and learning

NASA Astrophysics Data System (ADS)

Rabbani, Masoud; Montazeri, Mona; Farrokhi-Asl, Hamed; Rafiei, Hamed

2016-12-01

Mixed-model assembly lines are increasingly accepted in many industrial environments to meet the growing trend of greater product variability, diversification of customer demands, and shorter life cycles. In this research, a new mathematical model is presented considering balancing a mixed-model U-line and human-related issues, simultaneously. The objective function consists of two separate components. The first part of the objective function is related to balance problem. In this part, objective functions are minimizing the cycle time, minimizing the number of workstations, and maximizing the line efficiencies. The second part is related to human issues and consists of hiring cost, firing cost, training cost, and salary. To solve the presented model, two well-known multi-objective evolutionary algorithms, namely non-dominated sorting genetic algorithm and multi-objective particle swarm optimization, have been used. A simple solution representation is provided in this paper to encode the solutions. Finally, the computational results are compared and analyzed.

Technology advances in hospital practices: robotics in treatment of patients.

PubMed

Rosiek, Anna; Leksowski, Krzysztof

2015-06-01

Laparoscopic cholecystectomy is widely considered as the treatment of choice for acute cholecystitis. The safety of the procedure and its minimal invasiveness made it a valid treatment option for a patient not responding to antibiotic therapy. Our research shows that patients positively assess this treatment method, but the world's tendency is to turn to a more sophisticated method utilizing robot-assisted surgery as a gold standard. Providing patient with minimally invasive surgical procedures that utilize the state-of-the-art equipment like the da Vinci Robotic Surgical System underscores the commitment to high-quality patient care while enhancing patient safety. The advantages include minimal invasive scarring, less pain and bleeding, faster recovery time, and shorter hospital stay. The move toward less invasive and less morbid procedures and a need to re-create the true open surgical experience have paved the way for the development and application of robotic and computer-assisted systems in surgery in Poland as well as the rest of the world. © The Author(s) 2014.

Carrier-phase two-way satellite frequency transfer over a very long baseline

NASA Astrophysics Data System (ADS)

Fujieda, M.; Piester, D.; Gotoh, T.; Becker, J.; Aida, M.; Bauch, A.

2014-06-01

In this paper we report that carrier-phase two-way satellite time and frequency transfer (TWSTFT) was successfully demonstrated over a very long baseline of 9000 km, established between the National Institute of Information and Communications Technology (NICT) and the Physikalisch-Technische Bundesanstalt (PTB). We verified that the carrier-phase TWSTFT (TWCP) result agreed with those obtained by conventional TWSTFT and GPS carrier-phase (GPSCP) techniques. Moreover, a much improved short-term instability for frequency transfer of 2 × 10-13 at 1 s was achieved, which is at the same level as previously confirmed over a shorter baseline within Japan. The precision achieved was so high that the effects of ionospheric delay became significant; they are ignored in conventional TWSTFT even over a long link. We compensated for these effects using ionospheric delays computed from regional vertical total electron content maps. The agreement between the TWCP and GPSCP results was improved because of this compensation.

Martini straight: Boosting performance using a shorter cutoff and GPUs

NASA Astrophysics Data System (ADS)

de Jong, Djurre H.; Baoukina, Svetlana; Ingólfsson, Helgi I.; Marrink, Siewert J.

2016-02-01

In molecular dynamics simulations, sufficient sampling is of key importance and a continuous challenge in the field. The coarse grain Martini force field has been widely used to enhance sampling. In its original implementation, this force field applied a shifted Lennard-Jones potential for the non-bonded van der Waals interactions, to avoid problems related to a relatively short cutoff. Here we investigate the use of a straight cutoff Lennard-Jones potential with potential modifiers. Together with a Verlet neighbor search algorithm, the modified potential allows the use of GPUs to accelerate the computations in Gromacs. We find that this alternative potential has little influence on most of the properties studied, including partitioning free energies, bulk liquid properties and bilayer properties. At the same time, energy conservation is kept within reasonable bounds. We conclude that the newly proposed straight cutoff approach is a viable alternative to the standard shifted potentials used in Martini, offering significant speedup even in the absence of GPUs.

Sensorless control for permanent magnet synchronous motor using a neural network based adaptive estimator

NASA Astrophysics Data System (ADS)

Kwon, Chung-Jin; Kim, Sung-Joong; Han, Woo-Young; Min, Won-Kyoung

2005-12-01

The rotor position and speed estimation of permanent-magnet synchronous motor(PMSM) was dealt with. By measuring the phase voltages and currents of the PMSM drive, two diagonally recurrent neural network(DRNN) based observers, a neural current observer and a neural velocity observer were developed. DRNN which has self-feedback of the hidden neurons ensures that the outputs of DRNN contain the whole past information of the system even if the inputs of DRNN are only the present states and inputs of the system. Thus the structure of DRNN may be simpler than that of feedforward and fully recurrent neural networks. If the backpropagation method was used for the training of the DRNN the problem of slow convergence arise. In order to reduce this problem, recursive prediction error(RPE) based learning method for the DRNN was presented. The simulation results show that the proposed approach gives a good estimation of rotor speed and position, and RPE based training has requires a shorter computation time compared to backpropagation based training.

Automatic variable selection method and a comparison for quantitative analysis in laser-induced breakdown spectroscopy

NASA Astrophysics Data System (ADS)

Duan, Fajie; Fu, Xiao; Jiang, Jiajia; Huang, Tingting; Ma, Ling; Zhang, Cong

2018-05-01

In this work, an automatic variable selection method for quantitative analysis of soil samples using laser-induced breakdown spectroscopy (LIBS) is proposed, which is based on full spectrum correction (FSC) and modified iterative predictor weighting-partial least squares (mIPW-PLS). The method features automatic selection without artificial processes. To illustrate the feasibility and effectiveness of the method, a comparison with genetic algorithm (GA) and successive projections algorithm (SPA) for different elements (copper, barium and chromium) detection in soil was implemented. The experimental results showed that all the three methods could accomplish variable selection effectively, among which FSC-mIPW-PLS required significantly shorter computation time (12 s approximately for 40,000 initial variables) than the others. Moreover, improved quantification models were got with variable selection approaches. The root mean square errors of prediction (RMSEP) of models utilizing the new method were 27.47 (copper), 37.15 (barium) and 39.70 (chromium) mg/kg, which showed comparable prediction effect with GA and SPA.

Liver metastases: imaging considerations for protocol development with Multislice CT (MSCT)

PubMed Central

Silverman, Paul M

2006-01-01

Conventional, single-slice helical computed tomography (SSCT) allowed for scanning the majority of the liver during the critical portal venous phase. This was often referred to as the ‘optimal temporal window’. The introduction of current day multislice CT (MSCT) now allows us to acquire images in a much shorter time and more precisely than ever before. This yields increased conspicuity between low attenuation lesions and the enhanced normal liver parenchyma and optimal imaging for the vast majority of hepatic hypovascular metastases. Most importantly, these scanners, when compared to conventional non-helical scanners, avoid impinging upon the ‘equilibrium’ phase when tumors can become isodense/invisible. MSCT also allows for true multiphase scanning during the arterial and late arterial phases for detection of hypervascular metastases. The MSCT imaging speed has increased significantly over the past years with the introduction of 32- and 64-detector systems and will continue to increase in the future volumetric CT. This provides a number of important gains that are discussed in detail. PMID:17098650

Statistics of pressure and pressure gradient in homogeneous isotropic turbulence

NASA Technical Reports Server (NTRS)

Gotoh, T.; Rogallo, R. S.

1994-01-01

The statistics of pressure and pressure gradient in stationary isotropic turbulence are measured within direct numerical simulations at low to moderate Reynolds numbers. It is found that the one-point pdf of the pressure is highly skewed and that the pdf of the pressure gradient is of stretched exponential form. The power spectrum of the pressure P(k) is found to be larger than the corresponding spectrum P(sub G)(k) computed from a Gaussian velocity field having the same energy spectrum as that of the DNS field. The ratio P(k)/P(sub G)(k), a measure of the pressure-field intermittence, grows with wavenumber and Reynolds number as -R(sub lambda)(exp 1/2)log(k/k(sub d)) for k less than k(sub d)/2 where k(sub d) is the Kolmogorov wavenumber. The Lagrangian correlations of pressure gradient and velocity are compared and the Lagrangian time scale of the pressure gradient is observed to be much shorter than that of the velocity.

Specification of matrix cleanup goals in fractured porous media.

PubMed

Rodríguez, David J; Kueper, Bernard H

2013-01-01

Semianalytical transient solutions have been developed to evaluate what level of fractured porous media (e.g., bedrock or clay) matrix cleanup must be achieved in order to achieve compliance of fracture pore water concentrations within a specified time at specified locations of interest. The developed mathematical solutions account for forward and backward diffusion in a fractured porous medium where the initial condition comprises a spatially uniform, nonzero matrix concentration throughout the domain. Illustrative simulations incorporating the properties of mudstone fractured bedrock demonstrate that the time required to reach a desired fracture pore water concentration is a function of the distance between the point of compliance and the upgradient face of the domain where clean groundwater is inflowing. Shorter distances correspond to reduced times required to reach compliance, implying that shorter treatment zones will respond more favorably to remediation than longer treatment zones in which back-diffusion dominates the fracture pore water response. For a specified matrix cleanup goal, compliance of fracture pore water concentrations will be reached sooner for decreased fracture spacing, increased fracture aperture, higher matrix fraction organic carbon, lower matrix porosity, shorter aqueous phase decay half-life, and a higher hydraulic gradient. The parameters dominating the response of the system can be measured using standard field and laboratory techniques. © 2012, The Author(s). Ground Water © 2012, National Ground Water Association.

Duration of blastulation may be associated with ongoing pregnancy rate in single euploid blastocyst transfer cycles.

PubMed

Mumusoglu, Sezcan; Ozbek, Irem Y; Sokmensuer, Lale K; Polat, Mehtap; Bozdag, Gurkan; Papanikolaou, Evangelos; Yarali, Hakan

2017-12-01

Not all euploid embryos implant, necessitating additional tools to select viable blastocysts in preimplantation genetic screening cycles. In this retrospective cohort study, 129 consecutive patients who underwent 129 single euploid blastocyst transfers in cryopreserved embryo transfer cycles were included. All embryos were individually cultured in a time-lapse incubator from intracytoplasmic sperm injection up to trophoectoderm biopsy. Twenty-three time-lapse morphokinetic variables were tested among patients with (n = 68) or without (n = 61) ongoing pregnancy. All 23 time-lapse morphokinetic variables, apart from duration of blastulation (tB-tSB), were comparable between patients with or without ongoing pregnancy. Duration of blastulation was significantly shorter in patients with ongoing pregnancy (8.1 ± 3.2 versus 9.5 ± 3.4 h; P = 0.014); shorter duration of blastulation remained an independent predictor for ongoing pregnancy, when tested by logistic regression analysis (OR 0.81; 95% CI 0.70 to 0.93). One important limitation of this study, and a reason for caution, is the use of multiple comparisons, which can lead to differences at the 0.05 level simply by chance or random variation. Nonetheless, the study suggests that when more than one euploid blastocyst is available, priority might be given to those with a shorter duration of blastulation. Copyright © 2017 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.

Establishing the Basis for Validated Predictions of Highly Non-Equilibrium Flows. (With 9 Attachments)

DTIC Science & Technology

1993-10-14

expansion in Figure 8, a finite rate chemistry, inviscid flow solution was calculated using a One Dimensional Kinetics ( ODK ) computer program2 0...T Temperature range (K) 300 < T < 2000 Units cm3 mo-L’ sec-, [able 2: Reaction rate used in ODK compuiations. Working Gas 12 Stagnation pressure (atm...and proceeding to shorter wavelengths. The laser beam was focused on the probed volume with a 30 cm focal length lens. The LIF signal was collected in

Relativistic klystron driven compact high gradient accelerator as an injector to an X-ray synchrotron radiation ring

DOEpatents

Yu, David U. L.

1990-01-01

A compact high gradient accelerator driven by a relativistic klystron is utilized to inject high energy electrons into an X-ray synchrotron radiation ring. The high gradients provided by the relativistic klystron enables accelerator structure to be much shorter (typically 3 meters) than conventional injectors. This in turn enables manufacturers which utilize high energy, high intensity X-rays to produce various devices, such as computer chips, to do so on a cost effective basis.

Automated external defibrillators and simulated in-hospital cardiac arrests.

PubMed

Rossano, Joseph W; Jefferson, Larry S; Smith, E O'Brian; Ward, Mark A; Mott, Antonio R

2009-05-01

To test the hypothesis that pediatric residents would have shorter time to attempted defibrillation using automated external defibrillators (AEDs) compared with manual defibrillators (MDs). A prospective, randomized, controlled trial of AEDs versus MDs was performed. Pediatric residents responded to a simulated in-hospital ventricular fibrillation cardiac arrest and were randomized to using either an AED or MD. The primary end point was time to attempted defibrillation. Sixty residents, 21 (35%) interns, were randomized to 2 groups (AED = 30, MD = 30). Residents randomized to the AED group had a significantly shorter time to attempted defibrillation [median, 60 seconds (interquartile range, 53 to 71 seconds)] compared with those randomized to the MD group [median, 103 seconds (interquartile range, 68 to 288 seconds)] (P < .001). All residents in the AED group attempted defibrillation at <5 minutes compared with 23 (77%) in the MD group (P = .01). AEDs improve the time to attempted defibrillation by pediatric residents in simulated cardiac arrests. Further studies are needed to help determine the role of AEDs in pediatric in-hospital cardiac arrests.

Threshold units: A correct metric for reaction time?

PubMed Central

Zele, Andrew J.; Cao, Dingcai; Pokorny, Joel

2007-01-01

Purpose To compare reaction time (RT) to rod incremental and decremental stimuli expressed in physical contrast units or psychophysical threshold units. Methods Rod contrast detection thresholds and suprathreshold RTs were measured for Rapid-On and Rapid-Off ramp stimuli. Results Threshold sensitivity to Rapid-Off stimuli was higher than to Rapid-On stimuli. Suprathreshold RTs specified in Weber contrast for Rapid-Off stimuli were shorter than for Rapid-On stimuli. Reaction time data expressed in multiples of threshold reversed the outcomes: Reaction times for Rapid-On stimuli were shorter than those for Rapid-Off stimuli. The use of alternative contrast metrics also failed to equate RTs. Conclusions A case is made that the interpretation of RT data may be confounded when expressed in threshold units. Stimulus energy or contrast is the only metric common to the response characteristics of the cells underlying speeded responses. The use of threshold metrics for RT can confuse the interpretation of an underlying physiological process. PMID:17240416

Direct Measurements of Smartphone Screen-Time: Relationships with Demographics and Sleep

PubMed Central

Christensen, Matthew A.; Bettencourt, Laura; Kaye, Leanne; Moturu, Sai T.; Nguyen, Kaylin T.; Olgin, Jeffrey E.; Pletcher, Mark J.; Marcus, Gregory M.

2016-01-01

Background Smartphones are increasingly integrated into everyday life, but frequency of use has not yet been objectively measured and compared to demographics, health information, and in particular, sleep quality. Aims The aim of this study was to characterize smartphone use by measuring screen-time directly, determine factors that are associated with increased screen-time, and to test the hypothesis that increased screen-time is associated with poor sleep. Methods We performed a cross-sectional analysis in a subset of 653 participants enrolled in the Health eHeart Study, an internet-based longitudinal cohort study open to any interested adult (≥ 18 years). Smartphone screen-time (the number of minutes in each hour the screen was on) was measured continuously via smartphone application. For each participant, total and average screen-time were computed over 30-day windows. Average screen-time specifically during self-reported bedtime hours and sleeping period was also computed. Demographics, medical information, and sleep habits (Pittsburgh Sleep Quality Index–PSQI) were obtained by survey. Linear regression was used to obtain effect estimates. Results Total screen-time over 30 days was a median 38.4 hours (IQR 21.4 to 61.3) and average screen-time over 30 days was a median 3.7 minutes per hour (IQR 2.2 to 5.5). Younger age, self-reported race/ethnicity of Black and "Other" were associated with longer average screen-time after adjustment for potential confounders. Longer average screen-time was associated with shorter sleep duration and worse sleep-efficiency. Longer average screen-times during bedtime and the sleeping period were associated with poor sleep quality, decreased sleep efficiency, and longer sleep onset latency. Conclusions These findings on actual smartphone screen-time build upon prior work based on self-report and confirm that adults spend a substantial amount of time using their smartphones. Screen-time differs across age and race, but is similar across socio-economic strata suggesting that cultural factors may drive smartphone use. Screen-time is associated with poor sleep. These findings cannot support conclusions on causation. Effect-cause remains a possibility: poor sleep may lead to increased screen-time. However, exposure to smartphone screens, particularly around bedtime, may negatively impact sleep. PMID:27829040

The Effect of Life History on Retroviral Genome Invasions

PubMed Central

Kanda, Ravinder K.; Coulson, Tim

2015-01-01

Endogenous retroviruses (ERV), or the remnants of past retroviral infections that are no longer active, are found in the genomes of most vertebrates, typically constituting approximately 10% of the genome. In some vertebrates, particularly in shorter-lived species like rodents, it is not unusual to find active endogenous retroviruses. In longer-lived species, including humans where substantial effort has been invested in searching for active ERVs, it is unusual to find them; to date none have been found in humans. Presumably the chance of detecting an active ERV infection is a function of the length of an ERV epidemic. Intuitively, given that ERVs or signatures of past ERV infections are passed from parents to offspring, we might expect to detect more active ERVs in species with longer generation times, as it should take more years for an infection to run its course in longer than in shorter lived species. This means the observation of more active ERV infections in shorter compared to longer-lived species is paradoxical. We explore this paradox using a modeling approach to investigate factors that influence ERV epidemic length. Our simple epidemiological model may explain why we find evidence of active ERV infections in shorter rather than longer-lived species. PMID:25692467

Conditions for NIR fluorescence-guided tumor resectioning in preclinical lung cancer model (Conference Presentation)

NASA Astrophysics Data System (ADS)

Kim, Minji; Quan, Yuhua; Choi, Byeong Hyun; Choi, Yeonho; Kim, Hyun Koo; Kim, Beop-Min

2016-03-01

Pulmonary nodule could be identified by intraoperative fluorescence imaging system from systemic injection of indocyanine green (ICG) which achieves enhanced permeability and retention (EPR) effects. This study was performed to evaluate optimal injection time of ICG for detecting cancer during surgery in rabbit lung cancer model. VX2 carcinoma cell was injected in rabbit lung under fluoroscopic computed tomography-guidance. Solitary lung cancer was confirmed on positron emitting tomography with CT (PET/CT) 2 weeks after inoculation. ICG was administered intravenously and fluorescent intensity of lung tumor was measured using the custom-built intraoperative color and fluorescence merged imaging system (ICFIS) for 15 hours. Solitary lung cancer was resected through thoracoscopic version of ICFIS. ICG was observed in all animals. Because Lung has fast blood pulmonary circulation, Fluorescent signal showed maximum intensity earlier than previous studies in other organs. Fluorescent intensity showed maximum intensity within 6-9 hours in rabbit lung cancer. Overall, Fluorescent intensity decreased with increasing time, however, all tumors were detectable using fluorescent images until 12 hours. In conclusion, while there had been studies in other organs showed that optimal injection time was at least 24 hours before operation, this study showed shorter optimal injection time at lung cancer. Since fluorescent signal showed the maximum intensity within 6-9 hours, cancer resection could be performed during this time. This data informed us that optimal injection time of ICG should be evaluated in each different solid organ tumor for fluorescent image guided surgery.

Mining subspace clusters from DNA microarray data using large itemset techniques.

PubMed

Chang, Ye-In; Chen, Jiun-Rung; Tsai, Yueh-Chi

2009-05-01

Mining subspace clusters from the DNA microarrays could help researchers identify those genes which commonly contribute to a disease, where a subspace cluster indicates a subset of genes whose expression levels are similar under a subset of conditions. Since in a DNA microarray, the number of genes is far larger than the number of conditions, those previous proposed algorithms which compute the maximum dimension sets (MDSs) for any two genes will take a long time to mine subspace clusters. In this article, we propose the Large Itemset-Based Clustering (LISC) algorithm for mining subspace clusters. Instead of constructing MDSs for any two genes, we construct only MDSs for any two conditions. Then, we transform the task of finding the maximal possible gene sets into the problem of mining large itemsets from the condition-pair MDSs. Since we are only interested in those subspace clusters with gene sets as large as possible, it is desirable to pay attention to those gene sets which have reasonable large support values in the condition-pair MDSs. From our simulation results, we show that the proposed algorithm needs shorter processing time than those previous proposed algorithms which need to construct gene-pair MDSs.

Traffic Video Image Segmentation Model Based on Bayesian and Spatio-Temporal Markov Random Field

NASA Astrophysics Data System (ADS)

Zhou, Jun; Bao, Xu; Li, Dawei; Yin, Yongwen

2017-10-01

Traffic video image is a kind of dynamic image and its background and foreground is changed at any time, which results in the occlusion. In this case, using the general method is more difficult to get accurate image segmentation. A segmentation algorithm based on Bayesian and Spatio-Temporal Markov Random Field is put forward, which respectively build the energy function model of observation field and label field to motion sequence image with Markov property, then according to Bayesian' rule, use the interaction of label field and observation field, that is the relationship of label field’s prior probability and observation field’s likelihood probability, get the maximum posterior probability of label field’s estimation parameter, use the ICM model to extract the motion object, consequently the process of segmentation is finished. Finally, the segmentation methods of ST - MRF and the Bayesian combined with ST - MRF were analyzed. Experimental results: the segmentation time in Bayesian combined with ST-MRF algorithm is shorter than in ST-MRF, and the computing workload is small, especially in the heavy traffic dynamic scenes the method also can achieve better segmentation effect.

Are there age-related differences in learning to optimize speed, accuracy, and energy expenditure?

PubMed

Welsh, Timothy N; Higgins, Laura; Elliott, Digby

2007-12-01

Studies of age-related differences in manual aiming have indicated that older adults take longer to complete their movements than their younger counterparts because they tend to rely on time-consuming feedback-based control processes. Many authors have suggested that the reliance on feedback is the result of a "play-it-safe" strategy that has been adopted to compensate for a deterioration in accurate and consistent force generation. That is, perhaps because older adults know that their motor systems are not as reliable as the systems were at a younger age, they plan shorter movements that conserve time and space for feedback control to correct their programmed actions. The vast majority of the previous studies that have revealed these age-related differences in aiming, however, have used computer-based tasks that involve the transformation of perceptual into motor space. In the present experiment, older and younger adults completed real aiming movements over three sessions. The results suggest that, when acting in a real environment, the main difference between older and younger adults in movement execution lies in the efficient use of response-related feedback, not in the programming of movement.

A digital photogrammetric method for measuring horizontal surficial movements on the slumgullion earthflow, Hinsdale county, Colorado

USGS Publications Warehouse

Powers, P.S.; Chiarle, M.; Savage, W.Z.

1996-01-01

The traditional approach to making aerial photographic measurements uses analog or analytic photogrammetric equipment. We have developed a digital method for making measurements from aerial photographs which uses geographic information system (GIS) software, and primarily DOS-based personal computers. This method, which is based on the concept that a direct visual comparison can be made between images derived from two sets of aerial photographs taken at different times, was applied to the surface of the active portion of the Slumgullion earthflow in Colorado to determine horizontal displacement vectors from the movements of visually identifiable objects, such as trees and large rocks. Using this method, more of the slide surface can be mapped in a shorter period of time than using the standard photogrammetric approach. More than 800 horizontal displacement vectors were determined on the active earthflow surface using images produced by our digital photogrammetric technique and 1985 (1:12,000-scale) and 1990 (1:6,000-scale) aerial photographs. The resulting displacement field shows, with a 2-m measurement error (??? 10%), that the fastest moving portion of the landslide underwent 15-29 m of horizontal displacement between 1985 and 1990. Copyright ?? 1996 Elsevier Science Ltd.

Conformational Analysis on structural perturbations of the zinc finger NEMO

NASA Astrophysics Data System (ADS)

Godwin, Ryan; Salsbury, Freddie; Salsbury Group Team

2014-03-01

The NEMO (NF-kB Essential Modulator) Zinc Finger protein (2jvx) is a functional Ubiquitin-binding domain, and plays a role in signaling pathways for immune/inflammatory responses, apoptosis, and oncogenesis [Cordier et al., 2008]. Characterized by 3 cysteines and 1 histidine residue at the active site, the biologically occurring, bound zinc configuration is a stable structural motif. Perturbations of the zinc binding residues suggest conformational changes in the 423-atom protein characterized via analysis of all-atom molecular dynamics simulations. Structural perturbations include simulations with and without a zinc ion and with and without de-protonated cysteines, resulting in four distinct configurations. Simulations of various time scales show consistent results, yet the longest, GPU driven, microsecond runs show more drastic structural and dynamic fluctuations when compared to shorter duration time-scales. The last cysteine residue (26 of 28) and the helix on which it resides exhibit a secondary, locally unfolded conformation in addition to its normal bound conformation. Combined analytics elucidate how the presence of zinc and/or protonated cysteines impact the dynamics and energetic fluctuations of NEMO. Comprehensive Cancer Center of Wake Forest University Computational Biosciences shared resource supported by NCI CCSG P30CA012197.

[Endovascular interventions for multiple trauma].

PubMed

Kinstner, C; Funovics, M

2014-09-01

In recent years interventional radiology has significantly changed the management of injured patients with multiple trauma. Currently nearly all vessels can be reached within a reasonably short time with the help of specially preshaped catheters and guide wires to achieve bleeding control of arterial und venous bleeding. Whereas bleeding control formerly required extensive open surgery, current interventional methods allow temporary vessel occlusion (occlusion balloons), permanent embolization and stenting. In injured patients with multiple trauma preinterventional procedural planning is performed with the help of multidetector computed tomography whenever possible. Interventional radiology not only allows minimization of therapeutic trauma but also a considerably shorter treatment time. Interventional bleeding control has developed into a standard method in the management of vascular trauma of the chest and abdomen as well as in vascular injuries of the upper and lower extremities when open surgical access is associated with increased risk. Additionally, pelvic trauma, vascular trauma of the superior thoracic aperture and parenchymal arterial lacerations of organs that can be at least partially preserved are primarily managed by interventional methods. In an interdisciplinary setting interventional radiology provides a safe and efficient means of rapid bleeding control in nearly all vascular territories in addition to open surgical access.

Stochastic acceleration of electrons. I - Effects of collisions in solar flares

NASA Technical Reports Server (NTRS)

Hamilton, Russell J.; Petrosian, Vahe

1992-01-01

Stochastic acceleration of thermal electrons to nonrelativistic energies is studied under solar flare conditions. We show that, in turbulent regions, electron-whistler wave interactions can result in the acceleration of electrons in times comparable to or shorter than the Coulomb collision time. The kinetic equation describing the evolution of the electron energy distribution including stochastic acceleration by whistlers and energy loss via Coulomb interactions is solved for an initial thermal electron energy spectrum. In general, the shape of the resulting electron distributions are characterized by the energy E(c) where systematic energy gain by turbulence equals energy loss due to Coulomb collisions. For energies less than E(c), the spectra are steep (quasi-thermal) whereas above E(c), the spectra are power laws. We find that hard X-ray spectra computed using the electron distributions obtained from our numerical simulations are able to explain the complex spectral shapes and variations observed in impulsive hard X-ray bursts. In particular, we show that the gradual steepening observed by Lin et al. (1981) could be due to a systematic increase in the density of the plasma (due to evaporation) and the increasing importance of collisions instead of the appearance of a superhot thermal component.

Independent influence of gait speed and step length on stability and fall risk.

PubMed

Espy, D D; Yang, F; Bhatt, T; Pai, Y-C

2010-07-01

With aging, individuals' gaits become slower and their steps shorter; both are thought to improve stability against balance threats. Recent studies have shown that shorter step lengths, which bring the center of mass (COM) closer to the leading foot, improve stability against slip-related falls. However, a slower gait, hence lower COM velocity, does the opposite. Due to the inherent coupling of step length and speed in spontaneous gait, the extent to which the benefit of shorter steps can offset the slower speed is unknown. The purpose of this study was to investigate, through decoupling, the independent effects of gait speed and step length on gait stability and the likelihood of slip-induced falls. Fifty-seven young adults walked at one of three target gait patterns, two of equal speed and two of equal step length; at a later trial, they encountered an unannounced slip. The results supported our hypotheses that faster gait as well as shorter steps each ameliorates fall risk when a slip is encountered. This appeared to be attributable to the maintenance of stability from slip initiation to liftoff of the recovery foot during the slip. Successful decoupling of gait speed from step length reveals for the first time that, although slow gait in itself leads to instability and falls (a one-standard-deviation decrease in gait speed increases the odds of fall by 4-fold), this effect is offset by the related decrease in step length (the same one-standard-deviation decrease in step length lowers fall risk by 6 times). Copyright © 2010 Elsevier B.V. All rights reserved.

Duration of Antimicrobial Treatment for Bacteremia in Canadian Critically Ill Patients.

PubMed

Daneman, Nick; Rishu, Asgar H; Xiong, Wei; Bagshaw, Sean M; Dodek, Peter; Hall, Richard; Kumar, Anand; Lamontagne, Francois; Lauzier, Francois; Marshall, John; Martin, Claudio M; McIntyre, Lauralyn; Muscedere, John; Reynolds, Steve; Stelfox, Henry T; Cook, Deborah J; Fowler, Robert A

2016-02-01

The optimum duration of antimicrobial treatment for patients with bacteremia is unknown. Our objectives were to determine duration of antimicrobial treatment provided to patients who have bacteremia in ICUs, to assess pathogen/patient factors related to treatment duration, and to assess the relationship between treatment duration and survival. Retrospective cohort study. Fourteen ICUs across Canada. Patients with bacteremia and were present in the ICU at the time culture reported positive. Duration of antimicrobial treatment for patients who had bacteremia in ICU. Among 1,202 ICU patients with bacteremia, the median duration of treatment was 14 days, but with wide variability (interquartile range, 9-17.5). Most patient characteristics were not associated with treatment duration. Coagulase-negative staphylococci were the only pathogens associated with shorter treatment (odds ratio, 2.82; 95% CI, 1.51-5.26). The urinary tract was the only source of infection associated with a trend toward lower likelihood of shorter treatment (odds ratio, 0.67; 95% CI, 0.42-1.08); an unknown source of infection was associated with a greater likelihood of shorter treatment (odds ratio, 2.14; 95% CI, 1.17-3.91). The association of treatment duration and survival was unstable when analyzed based on timing of death. Critically ill patients who have bacteremia typically receive long courses of antimicrobials. Most patient/pathogen characteristics are not associated with treatment duration; survivor bias precludes a valid assessment of the association between treatment duration and survival. A definitive randomized controlled trial is needed to compare shorter versus longer antimicrobial treatment in patients who have bacteremia.

The influence of insurance status on waiting times in German acute care hospitals: an empirical analysis of new data

PubMed Central

2009-01-01

Background There is an ongoing debate in Germany about the assumption that patients with private health insurance (PHI) benefit from better access to medical care, including shorter waiting times (Lüngen et al. 2008), compared to patients with statutory health insurance (SHI). Problem Existing analyses of the determinants for waiting times in Germany are a) based on patient self-reports and b) do not cover the inpatient sector. This paper aims to fill both gaps by (i) generating new primary data and (ii) analyzing waiting times in German hospitals. Methods We requested individual appointments from 485 hospitals within an experimental study design, allowing us to analyze the impact of PHI versus SHI on waiting times (Asplin et al. 2005). Results In German acute care hospitals patients with PHI have significantly shorter waiting times than patients with SHI. Conclusion Discrimination in waiting times by insurance status does occur in the German acute hospital sector. Since there is very little transparency in treatment quality in Germany, we do not know whether discrimination in waiting times leads to discrimination in the quality of treatment. This is an important issue for future research. PMID:20025744

Acceleration of hepatobiliary dynamics in liver transplant donors.

PubMed

Aktaş, A; Koyuncu, A; Yalçin, H

2004-01-01

This study compared hepatobiliary scintigraphy findings in livers before and after liver graft donation to examine whether there is a change in hepatobiliary dynamics. Nine donors underwent hepatobiliary scintigraphy with intravenous injection of Tc-99m mebrofenin 1 day before and during the first week after left liver lobectomy. Five donors also underwent additional scintigraphy more than 1 year postsurgery. Images were acquired every second for the first minute, and then every minute for the next 40 minutes. Hepatic arterial perfusion index and portal perfusion index(PPI) were calculated from the images acquired during the first minute. For the function phase the computed parameters included: hepatic extraction efficiency, (HEE), time to appearance of activity in the intrahepatic biliary channels, and in the intestine, time to half maximal activity, and activity retained in the liver parenchyma at 40 minutes. Time to appearance of intrahepatic biliary channels and of intestinal activity was shorter among scintigraphies obtained within 1 week postsurgery compared to the preoperative values. Early after the operation HEE increased and PPI decreased significantly. Visual inspection of the scintigraphy scan obtained in all donors, within the first week postsurgery revealed hypertrophy of the right liver lobe. None of the patients showed progression of right lobe activity to the left side, even among scans obtained more than 1 year after donation. Reduced time to activity in the biliary channels and intestine and increased HEE suggest acceleration of hepatobiliary dynamics.

[Vocal recognition in dental and oral radiology].

PubMed

La Fianza, A; Giorgetti, S; Marelli, P; Campani, R

1993-10-01

Speech reporting benefits by units which can recognize sentences in any natural language in real time. The use of this method in the everyday practice of radiology departments shows its possible application fields. We used the speech recognition method to report orthopantomographic exams in order to evaluate the advantages the method offers to the management and quality of reporting the exams which are difficult to fit in other closed computed reporting systems. Both speech recognition and the conventional reporting method (tape recording and typewriting) were used to report 760 orthopantomographs. The average time needed to make the report, the legibility (or Flesch) index, as adapted for the Italian language, and finally a clinical index (the subjective opinion of 4 odontostomatologists) were evaluated for each exam, with both techniques. Moreover, errors in speech reporting (crude, human and overall errors) were also evaluated. The advantages of speech reporting consisted in the shorter time needed for the report to become available (2.24 vs 2.99 minutes) (p < 0.0005), in the improved Flesch index (30.62 vs 28.9) and in the clinical index. The data obtained from speech reporting in odontostomatologic radiology were useful not only to reduce the mean reporting time of orthopantomographic exams but also to improve report quality by reducing both grammar and transmission mistakes. However, the basic condition for such results to be obtained is the speaker's skills to make a good report.

The Usefulness of Virtual Fluoroscopic Preprocedural Planning During Percutaneous Transhepatic Biliary Drainage

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

Kinoshita, Mitsuhiro, E-mail: kinoshita.3216@tokushima-u.ac.jp; Shirono, Ryozo; Takechi, Katsuya

Purpose To retrospectively evaluate the usefulness of virtual fluoroscopic preprocedural planning (VFPP) in the percutaneous transhepatic biliary drainage (PTBD) procedure.Materials and MethodsTwenty-two patients who were treated by PTBD were included in this study. Twelve patients were treated using PTBD intraoperative referencing coronal computed tomography (CT) images (i.e., coronal CT group), and ten patients were treated using PTBD intraoperative referencing VFPP images (i.e., VFPP group). To analyze the effect of the intraoperative referencing VFPP image, the VFPP group was retrospectively compared with the coronal CT group.ResultsThe characteristics of both patient groups were not statistically significantly different. There were no significant differencesmore » in the targeted bile duct, diameter and depth of the target bile, breath-holding ability, number of targeted bile duct puncture attempts, change in the targeted bile duct, and exchange of the drainage catheter. However, the X-ray fluoroscopy time and the procedure time were significantly shorter in the VFPP group than in the coronal CT group (196 vs. 334 s, P < 0.05; and 16.0 vs. 27.2 min, P < 0.05).ConclusionIntraoperative referencing using the VFPP imaging in PTBD intuitively can be a useful tool for better localization of the guidewire in the bile duct and thereby shorten the X-ray fluoroscopy time and procedure time while minimizing radiation exposure and complications.« less

Mandibular reconstruction with the vascularized fibula flap: comparison of virtual planning surgery and conventional surgery.

PubMed

Wang, Y Y; Zhang, H Q; Fan, S; Zhang, D M; Huang, Z Q; Chen, W L; Ye, J T; Li, J S

2016-11-01

This study evaluated the accuracy of mandibular reconstruction and assessed clinical outcomes in both virtual planning and conventional surgery patients. ProPlan CMF surgical planning software was used preoperatively in the virtual planning group. In the virtual planning group, fibula flaps were harvested and osteotomized, and the mandibles were resected and reconstructed assisted by the prefabricated cutting guides and templates. The main outcome measures included the operative time, postoperative computed tomography (CT) scans, facial appearance, and occlusal function. The ischemia time and total operation time were shorter in the virtual planning group than in the conventional surgery group. High precision with the use of the cutting guides and templates was found for both the fibula and mandible, and a good fit was noted among the pre-bent plate, mandible, and fibula segments in the virtual planning group. Postoperative CT scans also showed excellent mandibular contours of the fibula flaps in accordance with virtual plans in the virtual planning group. This study demonstrated that virtual surgical planning was able to achieve more accurate mandibular reconstruction than conventional surgery. The use of prefabricated cutting guides and plates makes fibula flap moulding and placement easier, minimizes the operating time, and improves clinical outcomes. Copyright © 2016 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

A Kernel-based Lagrangian method for imperfectly-mixed chemical reactions

NASA Astrophysics Data System (ADS)

Schmidt, Michael J.; Pankavich, Stephen; Benson, David A.

2017-05-01

Current Lagrangian (particle-tracking) algorithms used to simulate diffusion-reaction equations must employ a certain number of particles to properly emulate the system dynamics-particularly for imperfectly-mixed systems. The number of particles is tied to the statistics of the initial concentration fields of the system at hand. Systems with shorter-range correlation and/or smaller concentration variance require more particles, potentially limiting the computational feasibility of the method. For the well-known problem of bimolecular reaction, we show that using kernel-based, rather than Dirac delta, particles can significantly reduce the required number of particles. We derive the fixed width of a Gaussian kernel for a given reduced number of particles that analytically eliminates the error between kernel and Dirac solutions at any specified time. We also show how to solve for the fixed kernel size by minimizing the squared differences between solutions over any given time interval. Numerical results show that the width of the kernel should be kept below about 12% of the domain size, and that the analytic equations used to derive kernel width suffer significantly from the neglect of higher-order moments. The simulations with a kernel width given by least squares minimization perform better than those made to match at one specific time. A heuristic time-variable kernel size, based on the previous results, performs on par with the least squares fixed kernel size.

Short-term versus long-term rainfall time series in the assessment of potable water savings by using rainwater in houses.

PubMed

Ghisi, Enedir; Cardoso, Karla Albino; Rupp, Ricardo Forgiarini

2012-06-15

The main objective of this article is to assess the possibility of using short-term instead of long-term rainfall time series to evaluate the potential for potable water savings by using rainwater in houses. The analysis was performed considering rainfall data from 1960 to 1995 for the city of Santa Bárbara do Oeste, located in the state of São Paulo, southeastern Brazil. The influence of the rainfall time series, roof area, potable water demand and percentage rainwater demand on the potential for potable water savings was evaluated. The potential for potable water savings was estimated using computer simulations considering a set of long-term rainfall time series and different sets of short-term rainfall time series. The ideal rainwater tank capacity was also assessed for some cases. It was observed that the higher the percentage rainwater demand and the shorter the rainfall time series, the larger the difference between the potential for potable water savings and the greater the variation in the ideal rainwater tank size. The sets of short-term rainfall time series considered adequate for different scenarios ranged from 1 to 13 years depending on the roof area, percentage rainwater demand and potable water demand. The main finding of the research is that sets of short-term rainfall time series can be used to assess the potential for potable water savings by using rainwater, as the results obtained are similar to those obtained from the long-term rainfall time series. Copyright © 2012 Elsevier Ltd. All rights reserved.

Affiliation and aggression as related to gender in domestic chicks (Gallus gallus).

PubMed

Vallortigara, G

1992-03-01

Social discrimination in male and female domestic chicks (Gallus gallus) was investigated by using (a) latencies of approach response, (b) simultaneous free choice, and (c) intersubject aggressive-pecking tests. In approach-response tests, females showed shorter latencies when tested with cagemates than when tested with strangers, whereas males showed shorter latencies when tested with strangers than when tested with cagemates. In simultaneous-choice tests, females spent more time near a cagemate, whereas males spent more time near a strange chick. In aggressive-pecking tests, both sexes pecked more at strangers than at cagemates; aggressive pecking at strangers, however, was higher in males than in females. It is argued that gender effects in social discrimination can be accounted for in terms of stronger social attachment in females and aggressive responses in males.

Modeling the Infrared Reverberation Response of the Circumnuclear Dusty Torus in AGNs: The Effects of Cloud Orientation and Anisotropic Illumination

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

Almeyda, Triana; Robinson, Andrew; Richmond, Michael

The obscuring circumnuclear torus of dusty molecular gas is one of the major components of active galactic nuclei (AGN). The torus can be studied by analyzing the time response of its infrared (IR) dust emission to variations in the AGN continuum luminosity, a technique known as reverberation mapping. The IR response is the convolution of the AGN ultraviolet/optical light curve with a transfer function that contains information about the size, geometry, and structure of the torus. Here, we describe a new computer model that simulates the reverberation response of a clumpy torus. Given an input optical light curve, the codemore » computes the emission of a 3D ensemble of dust clouds as a function of time at selected IR wavelengths, taking into account light travel delays. We present simulated dust emission responses at 3.6, 4.5, and 30 μ m that explore the effects of various geometrical and structural properties, dust cloud orientation, and anisotropy of the illuminating radiation field. We also briefly explore the effects of cloud shadowing (clouds are shielded from the AGN continuum source). Example synthetic light curves have also been generated, using the observed optical light curve of the Seyfert 1 galaxy NGC 6418 as input. The torus response is strongly wavelength-dependent, due to the gradient in cloud surface temperature within the torus, and because the cloud emission is strongly anisotropic at shorter wavelengths. Anisotropic illumination of the torus also significantly modifies the torus response, reducing the lag between the IR and optical variations.« less

Investigation of Thermal Effects of Photocoagulation on Retinal Tissue Using Fine-Motion-Sensitive Dynamic Optical Coherence Tomography.

PubMed

Kurokawa, Kazuhiro; Makita, Shuichi; Yasuno, Yoshiaki

2016-01-01

To enable an objective evaluation of photocoagulation, we characterize thermal tissue changes induced by laser irradiation with different laser parameters using optical coherence tomography (OCT). Spectral-domain OCT with a newly developed image processing method was used to monitor the thermal changes of ex vivo porcine retina. A sequence of OCT B-scans was obtained at the same retinal position simultaneously with the photocoagulation. Cross-sectional tissue displacement maps with respect to an OCT image taken before laser irradiation were computed for images taken before, during, and after laser irradiation, by using a correlation-based custom algorithm. Cross-sectional correlation maps (OCT correlation maps) were also computed from an OCT image taken before laser irradiation as a base-line to visualize alterations of tissue microstructure induced by laser irradiation. By systematically controlling laser power and exposure times, tissue displacements and structural changes of 200 retinal regions of 10 porcine eyes were characterized. Thermal tissue changes were characterized by B-scan images, OCT correlation maps, and tissue displacement maps. Larger tissue deformation was induced with higher laser power and shorter exposure time, while the same total laser energy (10 mJ) was applied. The measured tissue displacements revealed the complicated dynamics of tissue displacements. Three types of dynamics were observed; lateral expansion, lateral constriction, and a type showing more complicated dynamics. The results demonstrated the ability of this OCT-based method to evaluate retinal changes induced by laser irradiation. This evaluation could lead to further understanding of thermal effects, and increasing reproducibility of photocoagulation therapy.

19 CFR 210.15 - Motions.

Code of Federal Regulations, 2012 CFR

2012-04-01

... administrative law judge, all motions shall be addressed to the chief administrative law judge. During the time that an investigation or related proceeding is before an administrative law judge, all motions therein... written motions, or within such longer or shorter time as may be designated by the administrative law...

Do computer use, TV viewing, and the presence of the media in the bedroom predict school-aged children’s sleep habits in a longitudinal study?

PubMed Central

2013-01-01

Background Electronic media use is becoming an increasingly important part of life for today’s school-aged children. At the same time, concern of children’s sleep habits has arisen, and cross-sectional studies have shown that electronic media use is associated with short sleep duration and sleep disturbances. The purpose of this longitudinal study was to investigate whether baseline electronic media use and media presence in a child’s bedroom predicted sleep habits as well as changes in these sleep habits 18 months later among 10- to 11-year-old children in Finland. Methods The school-aged children (n=353, 51% girls) from 27 schools answered a questionnaire in 2006 and again 2008 in the Helsinki region of Finland. Electronic media use was measured by computer use and TV viewing. Media presence in a child’s bedroom means the presence of a TV or a computer in a child’s bedroom. Sleep habits were measured by bedtimes on school days and at the weekend days, sleep duration, discrepancy of bedtimes, and discrepancy of sleep duration between school days and weekends. Linear regression analyses were used to examine whether electronic media use and media presence predicted sleep habits with adjustments for grade, family structure, and baseline sleep. Gender differences were also examined. Results The children used a computer for one hour per day and watched TV over one hour a day in 2006. They slept over nine hours on school days and over ten hours at the weekends in 2008. Computer use and television viewing predicted significantly shorter sleep duration (p<0.001, p<0.05 respectively) and later bedtimes (p<0.001, p<0.01, respectively). Computer use also predicted unfavourable changes in sleep duration (p<0.001) and bedtimes on school days (p<0.001) and weekends (p<0.01). Among boys, media presence in the bedroom predicted poorer sleep habits and irregularity of sleep habits. Conclusions Computer use, TV viewing, and the presence of media in children’s bedrooms may reduce sleep duration, and delay bedtimes. PMID:23886318

Carcinoma of the apocrine glands of the anal sac in dogs: 113 cases (1985-1995).

PubMed

Williams, Laurel E; Gliatto, John M; Dodge, Richard K; Johnson, Jeffrey L; Gamblin, Rance M; Thamm, Douglas H; Lana, Susan E; Szymkowski, Mary; Moore, Antony S

2003-09-15

To characterize the signalment, clinical signs, biological behavior, and response to treatment of carcinoma of the apocrine glands of the anal sac in dogs. Retrospective study. 113 dogs with histologically confirmed carcinoma of the apocrine glands of the anal sac. Data on signalment, clinical signs, and staging were reviewed and analyzed along with treatment modality for potential association with survival time. Sex distribution was approximately equal (54% female, 46% male). One hundred four dogs underwent treatment consisting of surgery, radiation therapy, chemotherapy, or multimodal treatment. Median survival for treated dogs was 544 days (range, 0 to 1,873 days). Dogs treated with chemotherapy alone had significantly shorter survival (median, 212 days) than those receiving other treatments (median, 584 days). Dogs not treated with surgery had significantly shorter survival (median, 402 days) than those that underwent surgery as part of their treatment (median, 548 days). Dogs with tumors > or = 10 cm2 had significantly shorter survival (median, 292 days) than dogs with tumors < 10 cm2 (median, 584 days). Hypercalcemia was identified in 27% (n = 29) of dogs, and those dogs had significantly shorter survival (median, 256 days), compared with those that were normocalcemic (median, 584 days). Dogs with pulmonary metastasis had significantly shorter survival (median, 219 days) than dogs without evidence of pulmonary metastasis (median, 548 days). Unlike most previous reports, this study revealed an approximately equal sex distribution, and results suggest a more favorable prognosis.