A comparison of continuous- and discrete- time three-state models for rodent tumorigenicity experiments.

PubMed Central

Lindsey, J C; Ryan, L M

1994-01-01

The three-state illness-death model provides a useful way to characterize data from a rodent tumorigenicity experiment. Most parametrizations proposed recently in the literature assume discrete time for the death process and either discrete or continuous time for the tumor onset process. We compare these approaches with a third alternative that uses a piecewise continuous model on the hazards for tumor onset and death. All three models assume proportional hazards to characterize tumor lethality and the effect of dose on tumor onset and death rate. All of the models can easily be fitted using an Expectation Maximization (EM) algorithm. The piecewise continuous model is particularly appealing in this context because the complete data likelihood corresponds to a standard piecewise exponential model with tumor presence as a time-varying covariate. It can be shown analytically that differences between the parameter estimates given by each model are explained by varying assumptions about when tumor onsets, deaths, and sacrifices occur within intervals. The mixed-time model is seen to be an extension of the grouped data proportional hazards model [Mutat. Res. 24:267-278 (1981)]. We argue that the continuous-time model is preferable to the discrete- and mixed-time models because it gives reasonable estimates with relatively few intervals while still making full use of the available information. Data from the ED01 experiment illustrate the results. PMID:8187731

Field testing of three bedload samplers' efficiency in a gravel-bed river, Spitsbergen

NASA Astrophysics Data System (ADS)

Rachlewicz, Grzegorz; Zwoliński, Zbigniew; Kociuba, Waldemar; Stawska, Monika

2017-06-01

A comparative study of the three bedload traps was accomplished to determine the effectiveness differences between the devices. The research was carried out in two transverse sections of the proglacial, gravel-bedded Scott River (SW Svalbard) using three devices to perform direct measurements of bedload transport in the river channels. Several samplers are used for field measurements, but none of them has gained widespread acceptance as a standard so far. The paper compares transport rates collected in three bedload samplers that differ in structure and functionality: i) a portable Helley-Smith, pressure-difference bedload sampler (H-S), ii) an anchored River Bedload Trap (RBT), and iii) the portable sampler used by the Polish Hydrological Services (PIHM type C). All three samplers are constructed using the same components: a frame made of thin stainless steel sheet and a nylon bag with the same (2 mm) mesh size (except PIHM). Measurements were conducted within three consecutive days in two cross sections, in the same vertical profiles and at the same time (at intervals of 30 and 60 min). Measurements of bedload transport and water velocity were performed simultaneously. In order to determine the effectiveness and representativeness of short-term measurements using particular devices, the masses of the samples were converted into a specific rate of bedload transport and compared to the results of long-term continuous measurement (24 h measurement cycle). The results confirm that both specific transport indicators and the mass of the samples collected by the tested devices show a significant variation. Generally, the highest mass and specific transport indicators were obtained using the H-S sampler. The RBT produced moderate transport rates, while the PIHM sampler gave the lowest rates. The bedload transport rate in a profile estimated on the short-term measurements was compared to results of the continuous measurements conducted in the same cross sections. In the 7 cases we obtained underestimation (to max. 10 times) and in the next 7 cases - overestimation (to max. 114 times). Only in four cases were the results of short-term measurements similar to the continuous ones. The results obtained from the RBT sampler show the smallest variability among all tested devices.

Preferred Exertion across Three Common Modes of Exercise Training.

ERIC Educational Resources Information Center

Glass, Stephen C.; Chvala, Angela M.

2001-01-01

Examined the influence of exercise mode on self-selected exercise intensities. Participants performed three types of intensity tests. Researchers collected data on VO2 values continuously and recorded 1-minute averages several times for each submaximal test. Participants allowed to self-select exercise intensity chose work rates within the…

Implications For the Forest Products Industry

Treesearch

Richard A. Kluender

2001-01-01

Major changes have occurred in the Arkansas timber economy in the last 25 years.Global and domestic demand for forest products continues to expand,doubling every 42 years. Additionally,the U.S. per capita consumption rate of forest products is over three times the world average. Production continues to expand to meet rising global demand,but timber supplies have not...

Three real-time architectures - A study using reward models

NASA Technical Reports Server (NTRS)

Sjogren, J. A.; Smith, R. M.

1990-01-01

Numerous applications in the area of computer system analysis can be effectively studied with Markov reward models. These models describe the evolutionary behavior of the computer system by a continuous-time Markov chain, and a reward rate is associated with each state. In reliability/availability models, upstates have reward rate 1, and down states have reward rate zero associated with them. In a combined model of performance and reliability, the reward rate of a state may be the computational capacity, or a related performance measure. Steady-state expected reward rate and expected instantaneous reward rate are clearly useful measures which can be extracted from the Markov reward model. The diversity of areas where Markov reward models may be used is illustrated with a comparative study of three examples of interest to the fault tolerant computing community.

A Longitudinal Study of Childhood ADHD and Substance Dependence Disorders in Early Adulthood

PubMed Central

Breyer, Jessie L.; Lee, Susanne; Winters, Ken; August, Gerald; Realmuto, George

2014-01-01

Attention-deficit/hyperactivity disorder (ADHD) is a childhood disorder that is associated with many behavioral and social problems. These problems may continue when an individual continues to meet criteria for ADHD as an adult. In this study, we describe the outcome patterns for three different groups: individuals who had ADHD as children, but no longer meet criteria as adults (Childhood-Limited ADHD, n = 71); individuals who met ADHD criteria as children and continue to meet criteria as young adults (Persistent ADHD n = 79); and a control group of individuals who did not meet ADHD diagnostic criteria in childhood or adulthood (n = 69). Groups were compared to examine differences in change in rates of alcohol, marijuana, and nicotine dependence over three time points in young adulthood (mean ages 18, 20 and 22 years). The method used is notable as this longitudinal study followed participants from childhood into young adulthood instead of relying on retrospective self-reports from adult participants. Results indicated that there were no significant group differences in change in rates of substance dependence over time. However, individuals whose ADHD persisted into adulthood were significantly more likely to meet DSM-IV criteria for alcohol, marijuana, and nicotine dependence across the three time points after controlling for age, sex, childhood stimulant medication use, and childhood conduct problems. Implications of these findings, as well as recommendations for future research, are discussed. PMID:24731117

Real-time Continuous Assessment Method for Mental and Physiological Condition using Heart Rate Variability

NASA Astrophysics Data System (ADS)

Yoshida, Yutaka; Yokoyama, Kiyoko; Ishii, Naohiro

It is necessary to monitor the daily health condition for preventing stress syndrome. In this study, it was proposed the method assessing the mental and physiological condition, such as the work stress or the relaxation, using heart rate variability at real time and continuously. The instantanuous heart rate (HR), and the ratio of the number of extreme points (NEP) and the number of heart beats were calculated for assessing mental and physiological condition. In this method, 20 beats heart rate were used to calculate these indexes. These were calculated in one beat interval. Three conditions, which are sitting rest, performing mental arithmetic and watching relaxation movie, were assessed using our proposed algorithm. The assessment accuracies were 71.9% and 55.8%, when performing mental arithmetic and watching relaxation movie respectively. In this method, the mental and physiological condition was assessed using only 20 regressive heart beats, so this method is considered as the real time assessment method.

Viable Short-Term Directed Energy Weapon Naval Solutions: A Systems Analysis of Current Prototypes

DTIC Science & Technology

2013-06-01

Background and Issues for Congress 2013). The current DDG-51 electrical plant consists of three Gas Turbine Generator Sets ( GTGs ) rated at 2500 kW each...the generator rating (currently 2500kW), the practice is to have a minimum of two GTGs on line at all times to ensure continuity of service should...there be a system fault, or casualty to one of the GTGs (Mahoney, et al. 2010). This operation of at least two generators at all times essentially

Application of RNAMlet to surface defect identification of steels

NASA Astrophysics Data System (ADS)

Xu, Ke; Xu, Yang; Zhou, Peng; Wang, Lei

2018-06-01

As three main production lines of steels, continuous casting slabs, hot rolled steel plates and cold rolled steel strips have different surface appearances and are produced at different speeds of their production lines. Therefore, the algorithms for the surface defect identifications of the three steel products have different requirements for real-time and anti-interference. The existing algorithms cannot be adaptively applied to surface defect identification of the three steel products. A new method of adaptive multi-scale geometric analysis named RNAMlet was proposed. The idea of RNAMlet came from the non-symmetry anti-packing pattern representation model (NAM). The image is decomposed into a set of rectangular blocks asymmetrically according to gray value changes of image pixels. Then two-dimensional Haar wavelet transform is applied to all blocks. If the image background is complex, the number of blocks is large, and more details of the image are utilized. If the image background is simple, the number of blocks is small, and less computation time is needed. RNAMlet was tested with image samples of the three steel products, and compared with three classical methods of multi-scale geometric analysis, including Contourlet, Shearlet and Tetrolet. For the image samples with complicated backgrounds, such as continuous casting slabs and hot rolled steel plates, the defect identification rate obtained by RNAMlet was 1% higher than other three methods. For the image samples with simple backgrounds, such as cold rolled steel strips, the computation time of RNAMlet was one-tenth of the other three MGA methods, while the defect identification rates obtained by RNAMlet were higher than the other three methods.

Future of Mechatronics and Human

NASA Astrophysics Data System (ADS)

Harashima, Fumio; Suzuki, Satoshi

This paper mentions circumstance of mechatronics that sustain our human society, and introduces HAM(Human Adaptive Mechatronics)-project as one of research projects to create new human-machine system. The key point of HAM is skill, and analysis of skill and establishment of assist method to enhance total performance of human-machine system are main research concerns. As study of skill is an elucidation of human itself, analyses of human higher function are significant. In this paper, after surveying researches of human brain functions, an experimental analysis of human characteristic in machine operation is shown as one example of our research activities. We used hovercraft simulator as verification system including observation, voluntary motion control and machine operation that are needed to general machine operation. Process and factors to become skilled were investigated by identification of human control characteristics with measurement of the operator's line-of sight. It was confirmed that early switching of sub-controllers / reference signals in human and enhancement of space perception are significant.

Near real-time monitoring of volcanic surface deformation from GPS measurements at Long Valley Caldera, California

USGS Publications Warehouse

Ji, Kang Hyeun; Herring, Thomas A.; Llenos, Andrea L.

2013-01-01

Long Valley Caldera in eastern California is an active volcanic area and has shown continued unrest in the last three decades. We have monitored surface deformation from Global Positioning System (GPS) data by using a projection method that we call Targeted Projection Operator (TPO). TPO projects residual time series with secular rates and periodic terms removed onto a predefined spatial pattern. We used the 2009–2010 slow deflation as a target spatial pattern. The resulting TPO time series shows a detailed deformation history including the 2007–2009 inflation, the 2009–2010 deflation, and a recent inflation that started in late-2011 and is continuing at the present time (November 2012). The recent inflation event is about four times faster than the previous 2007–2009 event. A Mogi source of the recent event is located beneath the resurgent dome at about 6.6 km depth at a rate of 0.009 km3/yr volume change. TPO is simple and fast and can provide a near real-time continuous monitoring tool without directly looking at all the data from many GPS sites in this potentially eruptive volcanic system.

Effect of cycle run time of backwash and relaxation on membrane fouling removal in submerged membrane bioreactor treating sewage at higher flux.

PubMed

Tabraiz, Shamas; Haydar, Sajjad; Sallis, Paul; Nasreen, Sadia; Mahmood, Qaisar; Awais, Muhammad; Acharya, Kishor

2017-08-01

Intermittent backwashing and relaxation are mandatory in the membrane bioreactor (MBR) for its effective operation. The objective of the current study was to evaluate the effects of run-relaxation and run-backwash cycle time on fouling rates. Furthermore, comparison of the effects of backwashing and relaxation on the fouling behavior of membrane in high rate submerged MBR. The study was carried out on a laboratory scale MBR at high flux (30 L/m 2 ·h), treating sewage. The MBR was operated at three relaxation operational scenarios by keeping the run time to relaxation time ratio constant. Similarly, the MBR was operated at three backwashing operational scenarios by keeping the run time to backwashing time ratio constant. The results revealed that the provision of relaxation or backwashing at small intervals prolonged the MBR operation by reducing fouling rates. The cake and pores fouling rates in backwashing scenarios were far less as compared to the relaxation scenarios, which proved backwashing a better option as compared to relaxation. The operation time of backwashing scenario (lowest cycle time) was 64.6% and 21.1% more as compared to continuous scenario and relaxation scenario (lowest cycle time), respectively. Increase in cycle time increased removal efficiencies insignificantly, in both scenarios of relaxation and backwashing.

Control of algal production in a high rate algal pond: investigation through batch and continuous experiments.

PubMed

Derabe Maobe, H; Onodera, M; Takahashi, M; Satoh, H; Fukazawa, T

2014-01-01

For decades, arid and semi-arid regions in Africa have faced issues related to water availability for drinking, irrigation and livestock purposes. To tackle these issues, a laboratory scale greywater treatment system based on high rate algal pond (HRAP) technology was investigated in order to guide the operation of the pilot plant implemented in the 2iE campus in Ouagadougou (Burkina Faso). Because of the high suspended solids concentration generally found in effluents of this system, the aim of this study is to improve the performance of HRAPs in term of algal productivity and removal. To determine the selection mechanism of self-flocculated algae, three sets of sequencing batch reactors (SBRs) and three sets of continuous flow reactors (CFRs) were operated. Despite operation with the same solids retention time and the similarity of the algal growth rate found in these reactors, the algal productivity was higher in the SBRs owing to the short hydraulic retention time of 10 days in these reactors. By using a volume of CFR with twice the volume of our experimental CFRs, the algal concentration can be controlled during operation under similar physical conditions in both reactors.

The Demand for Higher Education in Puerto Rico.

ERIC Educational Resources Information Center

King, Jonathan

1993-01-01

Uses time-series data to estimate empirical enrollment functions for three Puerto Rico university systems. Measures opportunity cost and benefits to education as expected wage rates and tests a market segmentation process. Results show that the universities are not substitutes for one another. To cope with continuing revenue shortfalls,…

[Efficacy of different preparations of budesonide combined with pulmonary surfactant in the treatment of neonatal respiratory distress syndrome: a comparative analysis].

PubMed

Ke, Hua; Li, Zhan-Kui; Yu, Xi-Ping; Guo, Jin-Zhen

2016-05-01

To study the efficacy of different preparations of budesonide combined with pulmonary surfactant (PS) in improving blood gas levels and preventing bronchopulmonary dysplasia (BPD) in preterm infants with neonatal respiratory distress syndrome (NRDS). A total of 184 preterm infants who developed NRDS within 4 hours after birth were randomly administered with PS + continuous inhalation of budesonide aerosol (continuous aerosol group), PS+budesonide solution (solution group), PS + single inhalation of budesonide aerosol (single aerosol group), and PS alone, with 46 neonates in each group. The changes in arterial blood gas levels, rate of invasive mechanical ventilation after treatment, time of assisted ventilation, rate of repeated use of PS, and the incidence of BPD were compared between the four groups. On the 2nd to 4th day after treatment, pH, PCO2, and oxygenation index (FiO2/PaO2) showed significant differences among the four groups, and the continuous aerosol group showed the most improvements of all indicators, followed by the solution group, single aerosol group, and PS alone group. The continuous aerosol group had a significantly shorter time of assisted ventilation than the other three groups (P<0.05). The solution group had a significantly shorter time of assisted ventilation than the single aerosol and PS alone groups (P<0.05). The rate of invasive mechanical ventilation after treatment, rate of repeated use of PS, and incidence of BPD showed significant differences among the four groups (P<0.05), and the continuous aerosol group had the lowest rates, followed by the solution group. A combination of PS and continuous inhalation of budesonide aerosol has a better efficacy in the treatment of NRDS than a combination of PS and budesonide solution. The difference in reducing the incidence of BDP between the two administration methods awaits further investigation with a larger sample size.

Magnetic resonance cinematography of the fingers: a 3.0 Tesla feasibility study with comparison of incremental and continuous dynamic protocols.

PubMed

Bayer, Thomas; Adler, Werner; Janka, Rolf; Uder, Michael; Roemer, Frank

2017-12-01

To study the feasibility of magnetic resonance cinematography of the fingers (MRCF) with comparison of image quality of different protocols for depicting the finger anatomy during motion. MRCF was performed during a full flexion and extension movement in 14 healthy volunteers using a finger-gating device. Three real-time sequences (frame rates 17-59 images/min) and one proton density (PD) sequence (3 images/min) were acquired during incremental and continuous motion. Analyses were performed independently by three readers. Qualitative image analysis included Likert-scale grading from 0 (useless) to 5 (excellent) and specific visual analog scale (VAS) grading from 0 (insufficient) to 100 (excellent). Signal-to-noise calculation was performed. Overall percentage agreement and mean absolute disagreement were calculated. Within the real-time sequences a high frame-rate true fast imaging with steady-state free precession (TRUFI) yielded the best image quality with Likert and overall VAS scores of 3.0 ± 0.2 and 60.4 ± 25.3, respectively. The best sequence regarding image quality was an incremental PD with mean values of 4.8 ± 0.2 and 91.2 ± 9.4, respectively. Overall percentage agreement and mean absolute disagreement were 47.9 and 0.7, respectively. No statistically significant SNR differences were found between continuous and incremental motion for the real-time protocols. MRCF is feasible with appropriate image quality during continuous motion using a finger-gating device. Almost perfect image quality is achievable with incremental PD imaging, which represents a compromise for MRCF with the drawback of prolonged scanning time.

Calculating second derivatives of population growth rates for ecology and evolution

PubMed Central

Shyu, Esther; Caswell, Hal

2014-01-01

1. Second derivatives of the population growth rate measure the curvature of its response to demographic, physiological or environmental parameters. The second derivatives quantify the response of sensitivity results to perturbations, provide a classification of types of selection and provide one way to calculate sensitivities of the stochastic growth rate. 2. Using matrix calculus, we derive the second derivatives of three population growth rate measures: the discrete-time growth rate λ, the continuous-time growth rate r = log λ and the net reproductive rate R0, which measures per-generation growth. 3. We present a suite of formulae for the second derivatives of each growth rate and show how to compute these derivatives with respect to projection matrix entries and to lower-level parameters affecting those matrix entries. 4. We also illustrate several ecological and evolutionary applications for these second derivative calculations with a case study for the tropical herb Calathea ovandensis. PMID:25793101

Continuous ethanol production from cheese whey fermentation by Candida pseudotropicalis

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

Ghaly, A.E.; El-Taweel, A.A.

1997-12-01

Three pilot-scale continuous mix reactors of 5-L volume each were used to study the effects of retention time (18--42 hours) and initial substrate concentration (50--150 g/L) on the cell yield, lactose consumption, and maximum ethanol concentration during continuous fermentation of cheese whey using the yeast Candida pseudotropicalis. A microaeration rate of 480 mL/min and a nutrient supplement (yeast extract) concentration of 0.1% vol/vol were used. The results indicated that the dissolved oxygen concentration, temperature, cell concentration, lactose utilization rate, and ethanol concentration were affected by hydraulic retention time and initial substrate concentration. The highest cell concentration of 5.46 g/L andmore » the highest ethanol concentration of 57.96 g/L (with a maximum ethanol yield of 99.6% from the theoretical yield) were achieved at the 42-hour hydraulic retention time and the 150 g/L initial substrate concentration, whereas the highest cell yield was observed at the 50 g/L initial substrate concentration and the 36-hour hydraulic retention time. Lactose utilizations of 98, 91, and 83% were obtained with 50, 100, and 150 g/L initial substrate concentrations at the 42-hour hydraulic retention time. A pH control system was found unnecessary.« less

The Impact of Preterm Infants' Continuous Exposure to Breast Milk Odor on Stress Parameters: A Pilot Study.

PubMed

Maayan-Metzger, Ayala; Kedem-Friedrich, Peri; Bransburg Zabary, Sharron; Morag, Iris; Hemi, Rina; Kanety, Hannah; Strauss, Tzipora

2018-04-01

This pilot study aimed to assess the effect of continuous exposure to the odor of own mothers' breast milk (BM) on the stress parameters of preterm infants. Fifteen healthy preterm infants were included. Mean heart rate and salivary cortisol were measured over three consecutive time periods, each lasting 2 days: (1) preintervention (odor free); (2) intervention, during which a cotton pad soaked with 1.5 mL of BM was placed near the infant's head with the aim of providing continuous exposure to its odor; (3) postintervention period (odor free). Saliva cortisol levels differed significantly between the three exposure periods (pre-, during, and post-BM odor exposure): 11.38 ± 5.03, 9.51 ± 4.38, and 4.99 ± 3.42 nmol/L, respectively. A repeated univariate analysis of the cortisol measure showed a significant difference (F = 9.34; df = 2.28, p < 0.001). There was no difference in mean heart rate over the three study periods. Preterm infants exposed to BM odor from their own mothers demonstrate a persistent decrease in saliva cortisol levels, which continues after termination of the intervention. This finding may suggest that exposure to own mothers' BM odor has a soothing effect on preterm infants. Further randomized controlled studies are needed to evaluate this simple, safe, and inexpensive intervention.

Assessment Of Noise-induced Sleep Fragility In Two Age Ranges By Means Of Polysomnographic Microstructure

NASA Astrophysics Data System (ADS)

Terzano, M. G.; Parrino, L.; Spaggiari, M. C.; Buccino, G. P.; Fioriti, G.; Depoortere, H.

1993-04-01

The microstructure of sleep, which translates the short-lived fluctuations of the arousal level, is a commonly neglected feature in polysomnographic studies. Specifically arranged microstructural EEG events may provide important information on the dynamic characteristics of the sleep process. CAP (cyclic alternating pattern) and non-CAP are complementary modalities in which arousal-related "phasic" EEG phenomena are organized in non-REM sleep, and they correspond to opposite conditions of unstable and stable sleep depth, respectively. Thus, arousal instability can be measured by the CAP rate, the percentage ratio of total CAP time to total non-REM sleep time. The CAP rate, an age-related physiological variable that increases in several pathological conditions, is highly sensitive to acoustic perturbation. In the present study, two groups of healthy subjects without complaints about sleep, belonging to different age ranges (six young adults, three males and three females, between 20 and 30 years, and six middle-aged individuals, three males and three females, between 40 and 55 years) slept, after adaptation to the sleep laboratory, in a random sequence for two non-consecutive nights either under silent baseline (27·3 dB(A) Lcq) or noise-disturbed (continuous 55 dB(A) white noise) conditions. Age-related and noise-related effects on traditional sleep parameters and on the CAP rate were statistically evaluated by a split-plot test. Compared to young adults, the middle-aged individuals showed a significant reduction of total sleep time, stage 2 and REM sleep and significantly higher values of nocturnal awakenings and the CAP rate. The noisy nights were characterized by similar alterations. The disruptive effects of acoustic perturbation were greater on the more fragile sleep architecture of the older group. The increased fragility of sleep associated with aging probably reflects the decreased capacity of the sleeping brain to maintain steady states of vigilance. Total non-REM sleep described by traditional parameters was statistically unaffected during the disturbed nights, but the perturbing effects of noise on non-REM sleep stability and continuity were revealed by a significant increase in the CAP rate. The perspectives for a wide-ranging exploitation of this sleep parameter are discussed.

[Quick Start-up and Sustaining of Shortcut Nitrification in Continuous Flow Reactor].

PubMed

Wu, Peng; Zhang Shi-ying; Song, Yin-ling; Xu, Yue-zhong; Shen, Yao-liang

2016-04-15

How to achieve fast and stable startup of shortcut nitrification has a very important practical value for treatment of low C/N ratio wastewater. Thus, the quick start-up and sustaining of shortcut nitrification were investigated in continuous flow reactor targeting at the current situation of urban wastewater treatment plant using a continuous flow process. The results showed that quick start-up of shortcut nitrification could be successfully achieved in a continuous flow reactor after 60 days' operation with intermittent aeration and controlling of three stages of stop/aeration time (15 min/45 min, 45 min/45 min and 30 min/30 min). The nitrification rates could reach 90% or 95% respectively, while influent ammonia concentrations were 50 or 100 mg · L⁻¹ with stop/aeration time of 30 min/30 min. In addition, intermittent aeration could inhibit the activity of nitrite oxidizing bacteria (NOB), while short hydraulic retention time (HRT) may wash out NOB. And a combined use of both measures was beneficial to sustain shortcut nitrification.

Current Development in Treatment and Hydrogen Energy Conversion of Organic Solid Waste

NASA Astrophysics Data System (ADS)

Shin, Hang-Sik

2008-02-01

This manuscript summarized current developments on continuous hydrogen production technologies researched in Korea advanced institute of science and technology (KAIST). Long-term continuous pilot-scale operation of hydrogen producing processes fed with non-sterile food waste exhibited successful results. Experimental findings obtained by the optimization processes of growth environments for hydrogen producing bacteria, the development of high-rate hydrogen producing strategies, and the feasibility tests for real field application could contribute to the progress of fermentative hydrogen production technologies. Three major technologies such as controlling dilution rate depending on the progress of acidogenesis, maintaining solid retention time independently from hydraulic retention time, and decreasing hydrogen partial pressure by carbon dioxide sparging could enhance hydrogen production using anaerobic leaching beds reactors and anaerobic sequencing batch reactors. These findings could contribute to stable, reliable and effective performances of pilot-scale reactors treating organic wastes.

Versatile, High Quality and Scalable Continuous Flow Production of Metal-Organic Frameworks

PubMed Central

Rubio-Martinez, Marta; Batten, Michael P.; Polyzos, Anastasios; Carey, Keri-Constanti; Mardel, James I.; Lim, Kok-Seng; Hill, Matthew R.

2014-01-01

Further deployment of Metal-Organic Frameworks in applied settings requires their ready preparation at scale. Expansion of typical batch processes can lead to unsuccessful or low quality synthesis for some systems. Here we report how continuous flow chemistry can be adapted as a versatile route to a range of MOFs, by emulating conditions of lab-scale batch synthesis. This delivers ready synthesis of three different MOFs, with surface areas that closely match theoretical maxima, with production rates of 60 g/h at extremely high space-time yields. PMID:24962145

Quantum power functional theory for many-body dynamics

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

Schmidt, Matthias, E-mail: Matthias.Schmidt@uni-bayreuth.de

2015-11-07

We construct a one-body variational theory for the time evolution of nonrelativistic quantum many-body systems. The position- and time-dependent one-body density, particle current, and time derivative of the current act as three variational fields. The generating (power rate) functional is minimized by the true current time derivative. The corresponding Euler-Lagrange equation, together with the continuity equation for the density, forms a closed set of one-body equations of motion. Space- and time-nonlocal one-body forces are generated by the superadiabatic contribution to the functional. The theory applies to many-electron systems.

Dynamics of the sugar maple component of a white oak-yellow-poplar community

Treesearch

Richard C. Schlesinger

1989-01-01

The sugar maple (Acer saccharum Marsh) component in a southern Illinois forest increased over a 48-year period. By 1983 sugar maple was three times greater in importance than any other species in the stand. If the observed rate of increase were to continue, sugar maple would exclude all other species within another 50 to 60 years.

On the validity of Zeeman's classification for three dimensional competitive differential equations with linearly determined nullclines

NASA Astrophysics Data System (ADS)

Jiang, Jifa; Niu, Lei

2017-12-01

We study three dimensional competitive differential equations with linearly determined nullclines and prove that they always have 33 stable nullcline classes in total. Each class is given in terms of inequalities on the intrinsic growth rates and competitive coefficients and is independent of generating functions. The common characteristics are that every trajectory converges to an equilibrium in classes 1-25, that Hopf bifurcations do not occur within class 32, and that there is always a heteroclinic cycle in class 27. Nontrivial dynamical behaviors, such as the existence and multiplicity of limit cycles, only may occur in classes 26-33, but these nontrivial dynamical behaviors depend on generating functions. We show that Hopf bifurcation can occur within each of classes 26-31 for continuous-time Leslie/Gower system and Ricker system, the same as Lotka-Volterra system; but it only occurs in classes 26 and 27 for continuous-time Atkinson/Allen system and Gompertz system. There is an apparent distinction between Lotka-Volterra system and Leslie/Gower system, Ricker system, Atkinson/Allen system, and Gompertz system with the identical growth rate. Lotka-Volterra system with the identical growth rate has no limit cycle, but admits a center on the carrying simplex in classes 26 and 27. But Leslie/Gower system, Ricker system, Atkinson/Allen system, and Gompertz system with the identical growth rate do possess limit cycles. At last, we provide examples to show that Leslie/Gower system and Ricker system can also admit two limit cycles. This general classification greatly widens applications of Zeeman's method and makes it possible to investigate the existence and multiplicity of limit cycles, centers and stability of heteroclinic cycles for three dimensional competitive systems with linearly determined nullclines, as done in planar systems.

Joule heat production rate and the particle energy injection rate as a function of the geomagnetic indices AE and AL

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

Ahn, B.; Akasofu, S.; Kamide, Y.

1983-08-01

As a part of the joint efforts of operating six meridian chains of magnetometers during the IMS, magnetic records from 71 stations are used to deduce the distribution of electric fields and currents in the polar ionosphere for March 17, 18, and 19, 1978. As a continuation of this project, we have constructed hourly distribution maps of the Joule heat production rate and their sum over the entire polar region on the three days. For this purpose the conductivity distribution is inferred at each instant partially on the basis of an empirical method devised by Ahn et al. (1982). Themore » particle energy injection rate is estimated similarly by using an empirical method. The data set thus obtained allows us to estimate also the global Joule heat production rate U/sub J/, the global particle energy injection rate U/sub A/ and the sum U/sub Gamma/ of the two quantities. It is found that three global quantities (watt) are related almost linearly to the AE(nT) and AL(nT) indices. Our present estimates give the following relationships: U/sub J/ = 2.3 times 10/sup 8/ x AE/sub 8/ U/sub A/ = 0.6 times 10/sup 8/ x AE/sub 8/ and U/sub I/ = 2.9 times 10/sup 8/ x AE: U/sub J/ = 3.0 times 10/sup 8/ x AL/sub 8/ U/sub A/ = 0.8 times 10/sup 8/ x AL, and U/sub I/ = 3.8 times 10/sup 8/ x AL.« less

Spatial and temporal sensitivity of hydrogeomorphic responceand recovery to deforestation, Agriculture, and floods

USGS Publications Warehouse

Fitzpatrick, F.A.; Knox, J.C.

2000-01-01

Clear-cut logging followed by agricultural activity caused hydrologic and geomorphic changes in North Fish Creek, a Wisconsin tributary to Lake Superior. Hydro-geomorphic responses to changes in land use were sensitive to the location of reaches along the main stem and to the relative timing of large floods. Hydrologic and sediment-load modeling indicates that flood peaks were three times larger and sediment loads were five times larger during maximum agricultural activity in the 1920s and 1930s than prior to about 1890, when forest cover was dominant. Following logging, overbank sedimentation rates in the lower main stem increased four to six times above pre-settlement rates. Accelerated streambank and channel erosion in the upper main stem have been and continue to be primary sources of sediment to downstream reaches. Extreme floods in 1941 and 1946, followed by frequent moderate floods through 1954, caused extensive geomorphic changes along the entire main stem. Sedimentation rates in the lower main stem may have decreased in the last several decades as agricultural activity declined. However, geomorphic recovery is slow, as incised channels in the upper main stem function as efficient conveyors of watershed surface runoff and thereby continue to promote flooding and sedimentation problems downstream. [Key words: fluvial geomorphology, floods, erosion, sedimentation, deforestation, agriculture.].

Subjective and objective evaluation of visual fatigue on viewing 3D display continuously

NASA Astrophysics Data System (ADS)

Wang, Danli; Xie, Yaohua; Yang, Xinpan; Lu, Yang; Guo, Anxiang

2015-03-01

In recent years, three-dimensional (3D) displays become more and more popular in many fields. Although they can provide better viewing experience, they cause extra problems, e.g., visual fatigue. Subjective or objective methods are usually used in discrete viewing processes to evaluate visual fatigue. However, little research combines subjective indicators and objective ones in an entirely continuous viewing process. In this paper, we propose a method to evaluate real-time visual fatigue both subjectively and objectively. Subjects watch stereo contents on a polarized 3D display continuously. Visual Reaction Time (VRT), Critical Flicker Frequency (CFF), Punctum Maximum Accommodation (PMA) and subjective scores of visual fatigue are collected before and after viewing. During the viewing process, the subjects rate the visual fatigue whenever it changes, without breaking the viewing process. At the same time, the blink frequency (BF) and percentage of eye closure (PERCLOS) of each subject is recorded for comparison to a previous research. The results show that the subjective visual fatigue and PERCLOS increase with time and they are greater in a continuous process than a discrete one. The BF increased with time during the continuous viewing process. Besides, the visual fatigue also induced significant changes of VRT, CFF and PMA.

Modeling of Quasi-Four-Phase Flow in Continuous Casting Mold Using Hybrid Eulerian and Lagrangian Approach

NASA Astrophysics Data System (ADS)

Liu, Zhongqiu; Sun, Zhenbang; Li, Baokuan

2017-04-01

Lagrangian tracking model combined with Eulerian multi-phase model is employed to predict the time-dependent argon-steel-slag-air quasi-four-phase flow inside a slab continuous casting mold. The Eulerian approach is used for the description of three phases (molten steel, liquid slag, and air at the top of liquid slag layer). The dispersed argon bubble injected from the SEN is treated in the Lagrangian way. The complex interfacial momentum transfers between various phases are considered. Validation is supported by the measurement data of cold model experiments and industrial practice. Close agreements were achieved for the gas volume fraction, liquid flow pattern, level fluctuation, and exposed slag eye phenomena. Many known phenomena and new predictions were successfully reproduced using this model. The vortex slag entrapment phenomenon at the slag-steel interface was obtained using this model, some small slag drops are sucked deep into the liquid pool of molten steel. Varying gas flow rates have a large effect on the steel flow pattern in the upper recirculation zone. Three typical flow patterns inside the mold with different argon gas flow rates have been obtained: double roll, three roll, and single roll. Effects of argon gas flow rate, casting speed, and slag layer thickness on the exposed slag eye and level fluctuation at the slag-steel interface were studied. A dimensionless value of H ave/ h was proposed to describe the time-averaged level fluctuation of slag-steel interface. The exposed slag eye near the SEN would be formed when the value of H ave/ h is larger than 0.4.

Comparison of methods for calculating conditional expectations of sufficient statistics for continuous time Markov chains.

PubMed

Tataru, Paula; Hobolth, Asger

2011-12-05

Continuous time Markov chains (CTMCs) is a widely used model for describing the evolution of DNA sequences on the nucleotide, amino acid or codon level. The sufficient statistics for CTMCs are the time spent in a state and the number of changes between any two states. In applications past evolutionary events (exact times and types of changes) are unaccessible and the past must be inferred from DNA sequence data observed in the present. We describe and implement three algorithms for computing linear combinations of expected values of the sufficient statistics, conditioned on the end-points of the chain, and compare their performance with respect to accuracy and running time. The first algorithm is based on an eigenvalue decomposition of the rate matrix (EVD), the second on uniformization (UNI), and the third on integrals of matrix exponentials (EXPM). The implementation in R of the algorithms is available at http://www.birc.au.dk/~paula/. We use two different models to analyze the accuracy and eight experiments to investigate the speed of the three algorithms. We find that they have similar accuracy and that EXPM is the slowest method. Furthermore we find that UNI is usually faster than EVD.

On a class of unsteady three-dimensional Navier Stokes solutions relevant to rotating disc flows: Threshold amplitudes and finite time singularities

NASA Technical Reports Server (NTRS)

Hall, Philip; Balakumar, P.

1990-01-01

A class of exact steady and unsteady solutions of the Navier Stokes equations in cylindrical polar coordinates is given. The flows correspond to the motion induced by an infinite disc rotating with constant angular velocity about the z-axis in a fluid occupying a semi-infinite region which, at large distances from the disc, has velocity field proportional to (x,-y,O) with respect to a Cartesian coordinate system. It is shown that when the rate of rotation is large, Karman's exact solution for a disc rotating in an otherwise motionless fluid is recovered. In the limit of zero rotation rate a particular form of Howarth's exact solution for three-dimensional stagnation point flow is obtained. The unsteady form of the partial differential system describing this class of flow may be generalized to time-periodic equilibrium flows. In addition the unsteady equations are shown to describe a strongly nonlinear instability of Karman's rotating disc flow. It is shown that sufficiently large perturbations lead to a finite time breakdown of that flow whilst smaller disturbances decay to zero. If the stagnation point flow at infinity is sufficiently strong, the steady basic states become linearly unstable. In fact there is then a continuous spectrum of unstable eigenvalues of the stability equations but, if the initial value problem is considered, it is found that, at large values of time, the continuous spectrum leads to a velocity field growing exponentially in time with an amplitude decaying algebraically in time.

Continuous non-contact vital sign monitoring in neonatal intensive care unit

PubMed Central

Guazzi, Alessandro; Jorge, João; Davis, Sara; Watkinson, Peter; Green, Gabrielle; Shenvi, Asha; McCormick, Kenny; Tarassenko, Lionel

2014-01-01

Current technologies to allow continuous monitoring of vital signs in pre-term infants in the hospital require adhesive electrodes or sensors to be in direct contact with the patient. These can cause stress, pain, and also damage the fragile skin of the infants. It has been established previously that the colour and volume changes in superficial blood vessels during the cardiac cycle can be measured using a digital video camera and ambient light, making it possible to obtain estimates of heart rate or breathing rate. Most of the papers in the literature on non-contact vital sign monitoring report results on adult healthy human volunteers in controlled environments for short periods of time. The authors' current clinical study involves the continuous monitoring of pre-term infants, for at least four consecutive days each, in the high-dependency care area of the Neonatal Intensive Care Unit (NICU) at the John Radcliffe Hospital in Oxford. The authors have further developed their video-based, non-contact monitoring methods to obtain continuous estimates of heart rate, respiratory rate and oxygen saturation for infants nursed in incubators. In this Letter, it is shown that continuous estimates of these three parameters can be computed with an accuracy which is clinically useful. During stable sections with minimal infant motion, the mean absolute error between the camera-derived estimates of heart rate and the reference value derived from the ECG is similar to the mean absolute error between the ECG-derived value and the heart rate value from a pulse oximeter. Continuous non-contact vital sign monitoring in the NICU using ambient light is feasible, and the authors have shown that clinically important events such as a bradycardia accompanied by a major desaturation can be identified with their algorithms for processing the video signal. PMID:26609384

Continuous non-contact vital sign monitoring in neonatal intensive care unit.

PubMed

Villarroel, Mauricio; Guazzi, Alessandro; Jorge, João; Davis, Sara; Watkinson, Peter; Green, Gabrielle; Shenvi, Asha; McCormick, Kenny; Tarassenko, Lionel

2014-09-01

Current technologies to allow continuous monitoring of vital signs in pre-term infants in the hospital require adhesive electrodes or sensors to be in direct contact with the patient. These can cause stress, pain, and also damage the fragile skin of the infants. It has been established previously that the colour and volume changes in superficial blood vessels during the cardiac cycle can be measured using a digital video camera and ambient light, making it possible to obtain estimates of heart rate or breathing rate. Most of the papers in the literature on non-contact vital sign monitoring report results on adult healthy human volunteers in controlled environments for short periods of time. The authors' current clinical study involves the continuous monitoring of pre-term infants, for at least four consecutive days each, in the high-dependency care area of the Neonatal Intensive Care Unit (NICU) at the John Radcliffe Hospital in Oxford. The authors have further developed their video-based, non-contact monitoring methods to obtain continuous estimates of heart rate, respiratory rate and oxygen saturation for infants nursed in incubators. In this Letter, it is shown that continuous estimates of these three parameters can be computed with an accuracy which is clinically useful. During stable sections with minimal infant motion, the mean absolute error between the camera-derived estimates of heart rate and the reference value derived from the ECG is similar to the mean absolute error between the ECG-derived value and the heart rate value from a pulse oximeter. Continuous non-contact vital sign monitoring in the NICU using ambient light is feasible, and the authors have shown that clinically important events such as a bradycardia accompanied by a major desaturation can be identified with their algorithms for processing the video signal.

Adaptation of sleep and circadian rhythms to the Antarctic summer - A question of zeitgeber strength

NASA Technical Reports Server (NTRS)

Gander, Philippa H.; Macdonald, John A.; Montgomery, John C.; Paulin, Michael G.

1991-01-01

Adaptation of sleep and circadian rhythms was examined in three temperate zone dwellers arriving in Antarctica during summer. Rectal temperature, wrist activity, and heart rate were monitored continuously, sleep timing and quality noted on awakening, and mood and fatigue rated every 2 h while awake. Sleep was poorer in 2/3 subjects in Antarctica, where all subjects reported more difficulty rising. Sleep occurred at the same clock times in New Zealand and Antarctica, however, the rhythms of temperature, activity, and heart rate underwent a delay of about of 2 h. The subject with the most Antarctic experience had the least difficulty adapting to sleeping during constant daylight. The subject with the most delayed circadian rhythms had the most difficulty. The delay in the circadian system with respect to sleep and clock time is hypothesized to be due to differences in zeitgeber strength and/or zeitgeber exposure between Antarctica and New Zealand.

SIMULATION FROM ENDPOINT-CONDITIONED, CONTINUOUS-TIME MARKOV CHAINS ON A FINITE STATE SPACE, WITH APPLICATIONS TO MOLECULAR EVOLUTION.

PubMed

Hobolth, Asger; Stone, Eric A

2009-09-01

Analyses of serially-sampled data often begin with the assumption that the observations represent discrete samples from a latent continuous-time stochastic process. The continuous-time Markov chain (CTMC) is one such generative model whose popularity extends to a variety of disciplines ranging from computational finance to human genetics and genomics. A common theme among these diverse applications is the need to simulate sample paths of a CTMC conditional on realized data that is discretely observed. Here we present a general solution to this sampling problem when the CTMC is defined on a discrete and finite state space. Specifically, we consider the generation of sample paths, including intermediate states and times of transition, from a CTMC whose beginning and ending states are known across a time interval of length T. We first unify the literature through a discussion of the three predominant approaches: (1) modified rejection sampling, (2) direct sampling, and (3) uniformization. We then give analytical results for the complexity and efficiency of each method in terms of the instantaneous transition rate matrix Q of the CTMC, its beginning and ending states, and the length of sampling time T. In doing so, we show that no method dominates the others across all model specifications, and we give explicit proof of which method prevails for any given Q, T, and endpoints. Finally, we introduce and compare three applications of CTMCs to demonstrate the pitfalls of choosing an inefficient sampler.

Signaling on the continuous spectrum of nonlinear optical fiber.

PubMed

Tavakkolnia, Iman; Safari, Majid

2017-08-07

This paper studies different signaling techniques on the continuous spectrum (CS) of nonlinear optical fiber defined by nonlinear Fourier transform. Three different signaling techniques are proposed and analyzed based on the statistics of the noise added to CS after propagation along the nonlinear optical fiber. The proposed methods are compared in terms of error performance, distance reach, and complexity. Furthermore, the effect of chromatic dispersion on the data rate and noise in nonlinear spectral domain is investigated. It is demonstrated that, for a given sequence of CS symbols, an optimal bandwidth (or symbol rate) can be determined so that the temporal duration of the propagated signal at the end of the fiber is minimized. In effect, the required guard interval between the subsequently transmitted data packets in time is minimized and the effective data rate is significantly enhanced. Moreover, by selecting the proper signaling method and design criteria a distance reach of 7100 km is reported by only singling on CS at a rate of 9.6 Gbps.

Monitoring unrest in a large silicic caldera, the long Valley-inyo craters volcanic complex in east-central California

NASA Astrophysics Data System (ADS)

Hill, D. P.

1984-06-01

Recent patterns of geologic unrest in long Valley caldera in east-central California emphasize that this large, silicic volcanic system and the adjacent, geologically youthful Inyo-Mono Craters volcanic chain are still active and capable of producing locally hazardous volcanic eruptions. A series of four magnitude -6 earthquakes in May 1980 called attention to this current episode of unrest, and subsequent activity has included numerous earthquake swarms in the south moat of the caldera accompanied by inflation of the resurgent dome by more than 50 cm over the last five years. The seismicity associated with this unrest is currently monitored by a network of 31 telemetered seismic stations with an automatic processing system that yelds hypocentral locations and earthquake magnitudes in near-real time. Deformation of the ground is monitored by a) a series of overlapping trilateration networks that provide coverage ranging from annual measurements of regional deformation to daily measurements of deformation local to the active, southern section of the caldera, b) a regional network of level lines surveyed annually, c) a regional network of precise gravity stations occupied annually, d) local, L-shaped level figures surveyed every few months, and e) a network of fourteen borehole tiltmeter clusters (two instruments in each cluster) and a borehole dilatometer, the telemetered signals from which provide continuous data on deformation rates. Additional telemetered data provide continuous information on fluctuations in the local magnetic field, hydrogen gas emission rates at three sites, and water level and temperatures in three wells. Continuous data on disharge rates and temperatures from hot springs and fumaroles are collected by several on-site recorders within the caldera, and samples for liquid and gas chemistry are collected several times per year from selected hot springs and fumaroles.

Experimental and theoretical investigation of the stability of stepwise pH gradients in continuous flow electrophoresis

NASA Technical Reports Server (NTRS)

Kuhn, Reinhard; Wagner, Horst; Mosher, Richard A.; Thormann, Wolfgang

1987-01-01

Isoelectric focusing in the continuous flow mode can be more quickly and economically performed by admitting a stepwise pH gradient composed of simple buffers instead of uniform mixtures of synthetic carrier ampholytes. The time-consuming formation of the pH gradient by the electric field is thereby omitted. The stability of a three-step system with arginine - morpholinoethanesulfonic acid/glycylglycine - aspartic acid is analyzed theoretically by one-dimensional computer simulation as well as experimentally at various flow rates in a continuous flow apparatus. Excellent agreement between experimental and theoretical data was obtained. This metastable configuration was found to be suitable for focusing of proteins under continuous flow conditions. The influence of various combinations of electrolytes and membranes between electrophoresis chamber and electrode compartments is also discussed.

Hesitations in continuous tracking induced by a concurrent discrete task

NASA Technical Reports Server (NTRS)

Klapp, S. T.; Kelly, P. A.; Netick, A.

1985-01-01

Subjects performed a continuous visually-guided pursuit tracking task with the right hand. From time to time (intervals averaging 30 sec) an auditory tone appeared signaling the subjects to perform a discrete response with the left hand. The presence of this tone was frequently associated with a hesitation in right-hand tracking which lasted 1/3 sec or longer. The rate of occurrence of these hesitations was about the same when the left-hand response involved a choice between competing responses as when the left hand responded in a predetermined direction. Hesitations occurred for three different mechanical tracking manipulanda using different controlling muscles, and appeared to be due to freezing rather than to relaxation of muscular action. The rate of occurrence of hesitations declined with practice, and this improvement in right-hand performance was accompanied by an improvement in performance of the concurrent left-hand response. The presence of hesitations, and their reduction with practice, can be interpreted within several viewpoints.

A Single Chip Automotive Control LSI Using SOI Bipolar Complimentary MOS Double-Diffused MOS

NASA Astrophysics Data System (ADS)

Kawamoto, Kazunori; Mizuno, Shoji; Abe, Hirofumi; Higuchi, Yasushi; Ishihara, Hideaki; Fukumoto, Harutsugu; Watanabe, Takamoto; Fujino, Seiji; Shirakawa, Isao

2001-04-01

Using the example of an air bag controller, a single chip solution for automotive sub-control systems is investigated, by using a technological combination of improved circuits, bipolar complimentary metal oxide silicon double-diffused metal oxide silicon (BiCDMOS) and thick silicon on insulator (SOI). For circuits, an automotive specific reduced instruction set computer (RISC) center processing unit (CPU), and a novel, all integrated system clock generator, dividing digital phase-locked loop (DDPLL) are proposed. For the device technologies, the authors use SOI-BiCDMOS with trench dielectric-isolation (TD) which enables integration of various devices in an integrated circuit (IC) while avoiding parasitic miss operations by ideal isolation. The structures of the SOI layer and TD, are optimized for obtaining desired device characteristics and high electromagnetic interference (EMI) immunity. While performing all the air bag system functions over a wide range of supply voltage, and ambient temperature, the resulting single chip reduces the electronic parts to about a half of those in the conventional air bags. The combination of single chip oriented circuits and thick SOI-BiCDMOS technologies offered in this work is valuable for size reduction and improved reliability of automotive electronic control units (ECUs).

Optimization of L: -methionine feeding strategy for improving S-adenosyl-L: -methionine production by methionine adenosyltransferase overexpressed Pichia pastoris.

PubMed

Hu, Hui; Qian, Jiangchao; Chu, Ju; Wang, Yonghong; Zhuang, Yingping; Zhang, Siliang

2009-07-01

The recombinant Pichia pastoris harboring an improved methionine adenosyltransferase (MAT) shuffled gene was employed to biosynthesize S-adenosyl-L: -methionine (SAM). Two L: -methionine (L: -Met) addition strategies were used to supply the precursor: the batch addition strategy (L: -Met was added separately at three time points) and the continuous feeding strategies (L: -Met was fed continuously at the rate of 0.1, 0.2, and 0.5 g l(-1) h(-1), respectively). SAM accumulation, L: -Met conversion rate, and SAM productivity with the continuous feeding strategies were all improved over the batch addition strategy, which reached 8.46 +/- 0.31 g l(-1), 41.7 +/- 1.4%, and 0.18 +/- 0.01 g l(-1) h(-1) with the best continuous feeding strategy (0.2 g l(-1) h(-1)), respectively. The bottleneck for SAM production with the low L: -Met feeding rate (0.1 g L(-1) h(-1)) was the insufficient L: -Met supply. The analysis of the key enzyme activities indicated that the tricarboxylic acid cycle and glycolytic pathway were reduced with the increasing L: -Met feeding rate, which decreased the adenosine triphosphate (ATP) synthesis. The MAT activity also decreased as the L: -Met feeding rate rose. The reduced ATP synthesis and MAT activity were probably the reason for the low SAM accumulation when the L: -Met feeding rate reached 0.5 g l(-1) h(-1).

Measurement of respiratory rate and timing using a nasal thermocouple.

PubMed

Marks, M K; South, M; Carter, B G

1995-05-01

The aims of this study were to assess aspects of the response of a small thermocouple to temperature change, and to evaluate whether such a thermocouple could be used intermittently to measure respiratory rate and timing by detecting the changes in nasal temperature occurring with breathing. The study had three parts. First, three similar, fast-responding thermocouples were immersed repeatedly in warm water. Second, the influence of atmospheric temperature on the signal of a thermocouple placed at different sites within the nasal orifice was studied. The signals produced were continuously displayed and analyzed using a laptop computer to allow evaluation of the thermocouples' response characteristics. Third, simultaneous respiratory recordings were acquired using a nasal thermocouple and a nasal pneumotachograph in 12 teenaged subjects. The respiratory rate and the periods of time taken for inspiration (Ti) and expiration (Te) were calculated and compared. The thermocouples' responses to the temperature changes associated with breathing and immersion into water were rapid and consistent. The rate of the signals' decay, following the peak signal marking expiration, was influenced by the atmospheric temperature. The time constants of the thermocouples were similar (mean time constant = 0.41 sec, standard deviation (SD) = 0.07). Optimal respiratory recordings were obtained, with least discomfort, when the thermocouple was positioned at 0 to 4 mm within the nasal orifice. In comparing the respiratory recordings acquired simultaneously with a thermocouple and pneumotachograph, the respiratory rates were identical, and the Ti and Te values were similar (mean difference 0.04 sec (95% CI: -0.11 to 0.21 sec) and -0.04 sec (95% CI: -0.20 to 0.12 sec), respectively). Intermittent measurements of respiratory rate and timing using a nasal thermocouple accurately reflected measurements obtained from nasal airflow using a pneumotachograph.

Continuous background light significantly increases flashing-light enhancement of photosynthesis and growth of microalgae.

PubMed

Abu-Ghosh, Said; Fixler, Dror; Dubinsky, Zvy; Iluz, David

2015-01-01

Under specific conditions, flashing light enhances the photosynthesis rate in comparison to continuous illumination. Here we show that a combination of flashing light and continuous background light with the same integrated photon dose as continuous or flashing light alone can be used to significantly enhance photosynthesis and increase microalgae growth. To test this hypothesis, the green microalga Dunaliella salina was exposed to three different light regimes: continuous light, flashing light, and concomitant application of both. Algal growth was compared under three different integrated light quantities; low, intermediate, and moderately high. Under the combined light regime, there was a substantial increase in all algal growth parameters, with an enhanced photosynthesis rate, within 3days. Our strategy demonstrates a hitherto undescribed significant increase in photosynthesis and algal growth rates, which is beyond the increase by flashing light alone. Copyright © 2015 Elsevier Ltd. All rights reserved.

An adaptive Kalman filter approach for cardiorespiratory signal extraction and fusion of non-contacting sensors

PubMed Central

2014-01-01

Background Extracting cardiorespiratory signals from non-invasive and non-contacting sensor arrangements, i.e. magnetic induction sensors, is a challenging task. The respiratory and cardiac signals are mixed on top of a large and time-varying offset and are likely to be disturbed by measurement noise. Basic filtering techniques fail to extract relevant information for monitoring purposes. Methods We present a real-time filtering system based on an adaptive Kalman filter approach that separates signal offsets, respiratory and heart signals from three different sensor channels. It continuously estimates respiration and heart rates, which are fed back into the system model to enhance performance. Sensor and system noise covariance matrices are automatically adapted to the aimed application, thus improving the signal separation capabilities. We apply the filtering to two different subjects with different heart rates and sensor properties and compare the results to the non-adaptive version of the same Kalman filter. Also, the performance, depending on the initialization of the filters, is analyzed using three different configurations ranging from best to worst case. Results Extracted data are compared with reference heart rates derived from a standard pulse-photoplethysmographic sensor and respiration rates from a flowmeter. In the worst case for one of the subjects the adaptive filter obtains mean errors (standard deviations) of -0.2 min −1 (0.3 min −1) and -0.7 bpm (1.7 bpm) (compared to -0.2 min −1 (0.4 min −1) and 42.0 bpm (6.1 bpm) for the non-adaptive filter) for respiration and heart rate, respectively. In bad conditions the heart rate is only correctly measurable when the Kalman matrices are adapted to the target sensor signals. Also, the reduced mean error between the extracted offset and the raw sensor signal shows that adapting the Kalman filter continuously improves the ability to separate the desired signals from the raw sensor data. The average total computational time needed for the Kalman filters is under 25% of the total signal length rendering it possible to perform the filtering in real-time. Conclusions It is possible to measure in real-time heart and breathing rates using an adaptive Kalman filter approach. Adapting the Kalman filter matrices improves the estimation results and makes the filter universally deployable when measuring cardiorespiratory signals. PMID:24886253

An adaptive Kalman filter approach for cardiorespiratory signal extraction and fusion of non-contacting sensors.

PubMed

Foussier, Jerome; Teichmann, Daniel; Jia, Jing; Misgeld, Berno; Leonhardt, Steffen

2014-05-09

Extracting cardiorespiratory signals from non-invasive and non-contacting sensor arrangements, i.e. magnetic induction sensors, is a challenging task. The respiratory and cardiac signals are mixed on top of a large and time-varying offset and are likely to be disturbed by measurement noise. Basic filtering techniques fail to extract relevant information for monitoring purposes. We present a real-time filtering system based on an adaptive Kalman filter approach that separates signal offsets, respiratory and heart signals from three different sensor channels. It continuously estimates respiration and heart rates, which are fed back into the system model to enhance performance. Sensor and system noise covariance matrices are automatically adapted to the aimed application, thus improving the signal separation capabilities. We apply the filtering to two different subjects with different heart rates and sensor properties and compare the results to the non-adaptive version of the same Kalman filter. Also, the performance, depending on the initialization of the filters, is analyzed using three different configurations ranging from best to worst case. Extracted data are compared with reference heart rates derived from a standard pulse-photoplethysmographic sensor and respiration rates from a flowmeter. In the worst case for one of the subjects the adaptive filter obtains mean errors (standard deviations) of -0.2 min(-1) (0.3 min(-1)) and -0.7 bpm (1.7 bpm) (compared to -0.2 min(-1) (0.4 min(-1)) and 42.0 bpm (6.1 bpm) for the non-adaptive filter) for respiration and heart rate, respectively. In bad conditions the heart rate is only correctly measurable when the Kalman matrices are adapted to the target sensor signals. Also, the reduced mean error between the extracted offset and the raw sensor signal shows that adapting the Kalman filter continuously improves the ability to separate the desired signals from the raw sensor data. The average total computational time needed for the Kalman filters is under 25% of the total signal length rendering it possible to perform the filtering in real-time. It is possible to measure in real-time heart and breathing rates using an adaptive Kalman filter approach. Adapting the Kalman filter matrices improves the estimation results and makes the filter universally deployable when measuring cardiorespiratory signals.

Perceived Cooling Using Asymmetrically-Applied Hot and Cold Stimuli.

PubMed

Manasrah, Ahmad; Crane, Nathan; Guldiken, Rasim; Reed, Kyle B

2017-01-01

Temperature perception is a highly nonlinear phenomenon with faster rates of change being perceived at much lower thresholds than slower rates. This paper presents a method that takes advantage of this nonlinear characteristic to generate a perception of continuous cooling even though the average temperature is not changing. The method uses multiple thermal actuators so that a few are cooling quickly while the rest of the actuators are heating slowly. The slowly-heating actuators are below the perceptual threshold temperature change and hence are not perceived, while the quickly-cooling actuators are above the perceptual temperature change, hence are perceived. As a result, a feeling of decreasing temperature was elicited, when in fact, there was no net change in the temperature of the skin. Three sets of judiciously designed experiments were conducted in this study, investigating the effects of actuator sizes, forearm measurement locations, patterns of actuator layout, and various heating/cooling time cycles. Our results showed that 19 out 21 participants perceived the continuous cooling effect as hypothesized. Our research indicates that the measurement location, heating/cooling cycle times, and arrangement of the actuators affect the perception of continuous cooling.

The sequencing batch reactor as an excellent configuration to treat wastewater from the petrochemical industry.

PubMed

Caluwé, Michel; Daens, Dominique; Blust, Ronny; Geuens, Luc; Dries, Jan

2017-02-01

In the present study, the influence of a changing feeding pattern from continuous to pulse feeding on the characteristics of activated sludge was investigated with a wastewater from the petrochemical industry from the harbour of Antwerp. Continuous seed sludge, adapted to the industrial wastewater, was used to start up three laboratory-scale sequencing batch reactors. After an adaptation period from the shift to pulse feeding, the effect of an increasing organic loading rate (OLR) and volume exchange ratio (VER) were investigated one after another. Remarkable changes of the specific oxygen uptake rate (sOUR), microscopic structure, sludge volume index (SVI), SVI 30 /SVI 5 ratio, and settling rate were observed during adaptation. sOUR increased two to five times and treatment time decreased 43.9% in 15 days. Stabilization of the SVI occurred after a period of 20 days and improved significantly from 300 mL·g -1 to 80 mL·g -1 . Triplication of the OLR and VER had no negative influence on sludge settling and effluent quality. Adaptation time of the microorganisms to a new feeding pattern, OLR and VER was relatively short and sludge characteristics related to aerobic granular sludge were obtained. This study indicates significant potential of the batch activated sludge system for the treatment of this industrial petrochemical wastewater.

An online survey of chiropractors' opinions of continuing education

PubMed Central

Stuber, Kent J; Grod, Jaroslaw P; Smith, Dean L; Powers, Paul

2005-01-01

Background Continuing Education (CE) for chiropractors is mandatory for licensure in most North American jurisdictions. Numerous chiropractic colleges have begun collaborating with universities to offer master's degree programs. Distance education master's degree programs may be desirable to allow full-time practicing doctors to further their post-graduate education. The present survey sought to answer three questions. First, what is the level of satisfaction of chiropractors with their continuing education? Second, what is the level of interest of chiropractors in online master's degree programs? Lastly, what is the response rate of chiropractors to an online survey? Methods An online survey consisting of 22 multiple choice questions was e-mailed to 1000 chiropractors randomly selected from the mailing list of an online chiropractic newsletter. Upon completion of the questionnaire, participants' answers were saved on a secure site. Data analysis included evaluation of the demographic characteristics of the respondents, their opinions of and patterns of taking CE including online education, preferred learning formats, and their interest in proposed online master's degree programs. A survey response rate was determined. Results Nearly 86% of respondents felt their previously completed CE courses were either somewhat or extremely satisfactory. Over ninety percent of respondents who had completed online or distance CE coursesfound them to be somewhat or extremelysatisfactory. Almost half the respondents indicated that they most preferred online distance learning, while 34.08% most preferred face-to-face interaction. Fifty-three percent of respondents indicated an interest in starting a master's degree program; however 70.46% of respondents were interested in an online master's degree program that would offer CE credit. A response rate of 35.8% was obtained. Conclusion Satisfaction among chiropractors with CE programs is high. The notion of completing a part-time online master's degree (or online combined with face-to-face interaction) appears to be popular among respondents, with a M.Sc. in Chiropractic Sciences being the most popular of those mentioned. Online surveys are a viable method of obtaining opinion in a cost and time efficient manner; there are some sources of bias involved in this type of research, and numerous steps need to be taken to obtain a suitable response rate. PMID:16242035

Development of a digital video-microscopy technique to study lactose crystallisation kinetics in situ.

PubMed

Arellano, María Paz; Aguilera, José Miguel; Bouchon, Pedro

2004-11-15

Polarised light microscopy was employed non-invasively to monitor lactose crystallisation from non-seeded supersaturated solutions in real time. Images were continuously recorded, processed and characterised by image analysis, and the results were compared with those obtained by refractometry. Three crystallisation temperatures (10, 20 and 30 degrees C) and three different levels of initial relative supersaturation (C/C(s)=1.95; 2.34; 3.15) were investigated. Induction times using the imaging technique proved to be substantially lower than those determined using refractive index. Lactose crystals were isolated digitally to determine geometrical parameters of interest, such as perimeter, diameter, area, roundness and Feret mean, and to derive crystal growth rates. Mean growth rates obtained for single crystals were fitted to a combined mass transfer model (R(2)=0.9766). The model allowed the effects of temperature and supersaturation on crystallisation rate to be clearly identified. It also suggested that, in this set of experiments, surface integration seemed to be the rate controlling step. It is believed that a similar experimental set-up could be implemented in a real food system to characterise a particular process where crystallisation control is of interest and where traditional techniques are difficult to implement.

Individual variation in habituation: behaviour over time toward different stimuli in threespine sticklebacks (Gasterosteus aculeatus)

PubMed Central

Bell, Alison M.; Peeke, Harman V.S.

2014-01-01

Habituation, or the relatively permanent waning of a response as a result of repeated stimulation, is a form of behavioural plasticity that allows animals to filter out irrelevant stimuli and to focus selectively on important stimuli. Individuals that fail to habituate might be at a disadvantage if they continue to respond to irrelevant stimuli; therefore, habituation can have adaptive significance. In this study we compared rates of behaviour over time toward three different ecologically-relevant stimuli (food, a male intruder and a gravid female) in threespine sticklebacks (Gasterosteus aculeatus). We detected evidence for habituation to the stimuli, and males in this study were especially aggressive toward both male and female conspecifics. Although there were some clear temporal patterns that could be detected by looking at average behaviour, not all individuals behaved in the same ‘average’ way. We detected substantial inter-individual variation in behaviour toward all three stimuli, inter-individual variation in rates of habituation to both male and female conspecifics, but no evidence for correlations between behaviours across stimuli (behavioural syndromes). These results suggest that individual animals vary in rates of habituation, and prompt hypotheses about the causes and consequences of variation in rates of habituation. PMID:25678715

Enhanced oil recovery using flash-driven steamflooding

DOEpatents

Roark, Steven D.

1990-01-01

The present invention is directed to a novel steamflooding process which utilizes three specific stages of steam injection for enhanced oil recovery. The three stages are as follows: As steam is being injected into an oil-bearing reservoir through an injection well, the production rate of a production well located at a distance from the injection well is gradually restricted to a point that the pressure in the reservoir increases at a predetermined rate to a predetermined maximum value. After the maximum pressure has been reached, the production rate is increased to a value such that the predetermined maximum pressure value is maintained. Production at maximum pressure is continued for a length of time that will be unique for each individual reservoir. In some cases, this step of the steamflooding process of the invention may be omitted entirely. In the third stage of the steamflooding process of the invention, production rates at the producing well are increased gradually to allow the pressure to decrease down from the maximum pressure value to the original pressure value at the producing well. The rate of pressure reduction will be unique for each reservoir. After completing stage three, the three stages can be repeated or the steamflood may be terminated as considered desirable.

Effects of spacing of item repetitions in continuous recognition memory: does item retrieval difficulty promote item retention in older adults?

PubMed

Kılıç, Aslı; Hoyer, William J; Howard, Marc W

2013-01-01

BACKGROUND/STUDY CONTEXT: Older adults exhibit an age-related deficit in item memory as a function of the length of the retention interval, but older adults and young adults usually show roughly equivalent benefits due to the spacing of item repetitions in continuous memory tasks. The current experiment investigates the seemingly paradoxical effects of retention interval and spacing in young and older adults using a continuous recognition memory procedure. Fifty young adults and 52 older adults gave memory confidence ratings to words that were presented once (P1), twice (P2), or three times (P3), and the effects of the lag length and retention interval were assessed at P2 and at P3, respectively. Response times at P2 were disproportionately longer for older adults than for younger adults as a function of the number of items occurring between P1 and P2, suggestive of age-related loss in item memory. Ratings of confidence in memory responses revealed that older adults remembered fewer items at P2 with a high degree of certainty. Confidence ratings given at P3 suggested that young and older adults derived equivalent benefits from the spacing between P1 and P2. Findings of this study support theoretical accounts that suggest that recursive reminding and/or item retrieval difficulty promote item retention in older adults.

Optimization of passively mode-locked Nd:GdVO4 laser with the selectable pulse duration 15-70 ps

NASA Astrophysics Data System (ADS)

Frank, Milan; Jelínek, Michal; Vyhlídal, David; Kubeček, Václav

2016-12-01

In this paper the optimization of a continuously diode-pumped Nd:GdVO4 laser oscillator in bounce geometry passively mode-locked using semiconductor saturable absorber mirror is presented. In the previous results the Nd:GdVO4 laser system generating 30 ps pulses with the average output power of 6.9 W at the repetition rate of 200 MHz at the wavelength of 1063 nm was reported. Now we are demonstrating up to three times increase of peak power due to the optimization of mode-matching in the laser resonator. Depending on the oscillator configuration we obtained the stable continuously mode-locked operation with pulses having selectable duration from 15 ps to 70 ps with the average output power of 7 W and the repetition rate of 150 MHz.

Concordance of Motion Sensor and Clinician-Rated Fall Risk Scores in Older Adults.

PubMed

Elledge, Julie

2017-12-01

As the older adult population in the United States continues to grow, developing reliable, valid, and practical methods for identifying fall risk is a high priority. Falls are prevalent in older adults and contribute significantly to morbidity and mortality rates and rising health costs. Identifying at-risk older adults and intervening in a timely manner can reduce falls. Conventional fall risk assessment tools require a health professional trained in the use of each tool for administration and interpretation. Motion sensor technology, which uses three-dimensional cameras to measure patient movements, is promising for assessing older adults' fall risk because it could eliminate or reduce the need for provider oversight. The purpose of this study was to assess the concordance of fall risk scores as measured by a motion sensor device, the OmniVR Virtual Rehabilitation System, with clinician-rated fall risk scores in older adult outpatients undergoing physical rehabilitation. Three standardized fall risk assessments were administered by the OmniVR and by a clinician. Validity of the OmniVR was assessed by measuring the concordance between the two assessment methods. Stability of the OmniVR fall risk ratings was assessed by measuring test-retest reliability. The OmniVR scores showed high concordance with the clinician-rated scores and high stability over time, demonstrating comparability with provider measurements.

The development of fixed-ratio performance under the influence of ribonucleic acid12

PubMed Central

Gott, C. Thomas; Weiss, Bernard

1972-01-01

The transition from fixed-ratio 1 performance (every response reinforced) to fixed-ratio 30 performance (every thirtieth response reinforced) was studied in nine pigeons. These were divided into three treatment groups given daily oral doses of saline, or 250 mg/kg/day or 500 mg/kg/day of yeast ribonucleic acid. Detailed computer-assisted analyses of how fixed-ratio behavior develops revealed the following typical sequence. After the transition, the first few ratios typically were emitted without long interresponse times within the ratio. Steady responding then ceased, and numerous long interresponse times occurred, with no systematic relationship to ordinal position within the ratio. Gradually, a new pattern evolved, characterized by a consistently long post-reinforcement time, a border region of the next few interresponse times within which the mean interresponse time monotonically decreased, and short interresponse times within the last 80% of the ratio. Long interresponse times were eliminated from this last section of the ratio without regard to proximity to reinforcement. Various analytical procedures suggested that the final pattern can be conceived, in part, as the shaping of a reliable response topography. The group of three pigeons given 250 mg/kg/day of yeast ribonucleic acid responded at higher rates than the saline and 500 mg/kg/day groups. The latter group, in contrast to the saline and lower dose groups, which continued to increase their rates, reached a rate asymptote very early. PMID:4574711

Continuous high speed coherent one-way quantum key distribution.

PubMed

Stucki, Damien; Barreiro, Claudio; Fasel, Sylvain; Gautier, Jean-Daniel; Gay, Olivier; Gisin, Nicolas; Thew, Rob; Thoma, Yann; Trinkler, Patrick; Vannel, Fabien; Zbinden, Hugo

2009-08-03

Quantum key distribution (QKD) is the first commercial quantum technology operating at the level of single quanta and is a leading light for quantum-enabled photonic technologies. However, controlling these quantum optical systems in real world environments presents significant challenges. For the first time, we have brought together three key concepts for future QKD systems: a simple high-speed protocol; high performance detection; and integration both, at the component level and for standard fibre network connectivity. The QKD system is capable of continuous and autonomous operation, generating secret keys in real time. Laboratory and field tests were performed and comparisons made with robust InGaAs avalanche photodiodes and superconducting detectors. We report the first real world implementation of a fully functional QKD system over a 43 dB-loss (150 km) transmission line in the Swisscom fibre optic network where we obtained average real-time distribution rates over 3 hours of 2.5 bps.

Change in the Mechanical Energy of the Body Center of Mass in Hemiplegic Gait after Continuous Use of a Plantar Flexion Resistive Ankle-foot Orthosis.

PubMed

Haruna, Hirokazu; Sugihara, Shunichi; Kon, Keisuke; Miyasaka, Tomoya; Hayakawa, Yasuyuki; Nosaka, Toshiya; Kimura, Kazuyuki

2013-11-01

[Purpose] The aim of this study was to investigate the changes in mechanical energy due to continuous use of a plantar flexion resistive ankle-foot orthosis (AFO) of subjects with chronic hemiplegia. [Subjects and Methods] The subjects were 5 hemiplegic patients using AFOs without a plantar flexion resistive function in their daily lives. We analyzed the gait of the subjects using a 3D motion capture system under three conditions: patients' use of their own AFOs; after being fitted with a plantar flexion resistive AFO; and after continuous use of the device. The gait efficiency was determined by calculating the mutual exchange of kinetic and potential energy of the center of mass. [Results] An increased exchange rate of the kinetic and potential energy was found for all subjects. A larger increase of energy exchange was shown on the non-paralyzed side, and after continuous use of the plantar flexion resistive AFO. [Conclusion] We found that continuous use of a plantar flexion resistive AFO increased the rate of mutual exchange between kinetic energy and potential energy. The change in the rate was closely related to the role of the non-paretic side, showing that the subjects needed a certain amount of time to adapt to the plantar flexion resistive AFO.

An alternative view of continuous forest inventories

Treesearch

Francis A. Roesch

2008-01-01

A generalized three-dimensional concept of continuous forest inventories applicable to all common forest sample designs is presented and discussed. The concept recognizes the forest through time as a three-dimensional population, two dimensions in land area and the third in time. The sample is selected from a finite three-dimensional partitioning of the population. The...

Three-Dimensional Super-Resolution: Theory, Modeling, and Field Tests Results

NASA Technical Reports Server (NTRS)

Bulyshev, Alexander; Amzajerdian, Farzin; Roback, Vincent E.; Hines, Glenn; Pierrottet, Diego; Reisse, Robert

2014-01-01

Many flash lidar applications continue to demand higher three-dimensional image resolution beyond the current state-of-the-art technology of the detector arrays and their associated readout circuits. Even with the available number of focal plane pixels, the required number of photons for illuminating all the pixels may impose impractical requirements on the laser pulse energy or the receiver aperture size. Therefore, image resolution enhancement by means of a super-resolution algorithm in near real time presents a very attractive solution for a wide range of flash lidar applications. This paper describes a superresolution technique and illustrates its performance and merits for generating three-dimensional image frames at a video rate.

Apparent diffusion coefficient histogram analysis can evaluate radiation-induced parotid damage and predict late xerostomia degree in nasopharyngeal carcinoma

PubMed Central

Zhou, Nan; Guo, Tingting; Zheng, Huanhuan; Pan, Xia; Chu, Chen; Dou, Xin; Li, Ming; Liu, Song; Zhu, Lijing; Liu, Baorui; Chen, Weibo; He, Jian; Yan, Jing; Zhou, Zhengyang; Yang, Xiaofeng

2017-01-01

We investigated apparent diffusion coefficient (ADC) histogram analysis to evaluate radiation-induced parotid damage and predict xerostomia degrees in nasopharyngeal carcinoma (NPC) patients receiving radiotherapy. The imaging of bilateral parotid glands in NPC patients was conducted 2 weeks before radiotherapy (time point 1), one month after radiotherapy (time point 2), and four months after radiotherapy (time point 3). From time point 1 to 2, parotid volume, skewness, and kurtosis decreased (P < 0.001, = 0.001, and < 0.001, respectively), but all other ADC histogram parameters increased (all P < 0.001, except P = 0.006 for standard deviation [SD]). From time point 2 to 3, parotid volume continued to decrease (P = 0.022), and SD, 75th and 90th percentiles continued to increase (P = 0.024, 0.010, and 0.006, respectively). Early change rates of parotid ADCmean, ADCmin, kurtosis, and 25th, 50th, 75th, 90th percentiles (from time point 1 to 2) correlated with late parotid atrophy rate (from time point 1 to 3) (all P < 0.05). Multiple linear regression analysis revealed correlations among parotid volume, time point, and ADC histogram parameters. Early mean change rates for bilateral parotid SD and ADCmax could predict late xerostomia degrees at seven months after radiotherapy (three months after time point 3) with AUC of 0.781 and 0.818 (P = 0.014, 0.005, respectively). ADC histogram parameters were reproducible (intraclass correlation coefficient, 0.830 - 0.999). ADC histogram analysis could be used to evaluate radiation-induced parotid damage noninvasively, and predict late xerostomia degrees of NPC patients treated with radiotherapy. PMID:29050274

Apparent diffusion coefficient histogram analysis can evaluate radiation-induced parotid damage and predict late xerostomia degree in nasopharyngeal carcinoma.

PubMed

Zhou, Nan; Guo, Tingting; Zheng, Huanhuan; Pan, Xia; Chu, Chen; Dou, Xin; Li, Ming; Liu, Song; Zhu, Lijing; Liu, Baorui; Chen, Weibo; He, Jian; Yan, Jing; Zhou, Zhengyang; Yang, Xiaofeng

2017-09-19

We investigated apparent diffusion coefficient (ADC) histogram analysis to evaluate radiation-induced parotid damage and predict xerostomia degrees in nasopharyngeal carcinoma (NPC) patients receiving radiotherapy. The imaging of bilateral parotid glands in NPC patients was conducted 2 weeks before radiotherapy (time point 1), one month after radiotherapy (time point 2), and four months after radiotherapy (time point 3). From time point 1 to 2, parotid volume, skewness, and kurtosis decreased ( P < 0.001, = 0.001, and < 0.001, respectively), but all other ADC histogram parameters increased (all P < 0.001, except P = 0.006 for standard deviation [SD]). From time point 2 to 3, parotid volume continued to decrease ( P = 0.022), and SD, 75 th and 90 th percentiles continued to increase ( P = 0.024, 0.010, and 0.006, respectively). Early change rates of parotid ADC mean , ADC min , kurtosis, and 25 th , 50 th , 75 th , 90 th percentiles (from time point 1 to 2) correlated with late parotid atrophy rate (from time point 1 to 3) (all P < 0.05). Multiple linear regression analysis revealed correlations among parotid volume, time point, and ADC histogram parameters. Early mean change rates for bilateral parotid SD and ADC max could predict late xerostomia degrees at seven months after radiotherapy (three months after time point 3) with AUC of 0.781 and 0.818 ( P = 0.014, 0.005, respectively). ADC histogram parameters were reproducible (intraclass correlation coefficient, 0.830 - 0.999). ADC histogram analysis could be used to evaluate radiation-induced parotid damage noninvasively, and predict late xerostomia degrees of NPC patients treated with radiotherapy.

Stress loading from viscous flow in the lower crust and triggering of aftershocks following the 1994 Northridge, California, earthquake

USGS Publications Warehouse

Deng, J.; Hudnut, K.; Gurnis, M.; Hauksson, E.

1999-01-01

Following the M(w) 6.7 Northridge earthquake, significant postseismic displacements were resolved with GPS. Using a three-dimensional viscoelastic model, we suggest that this deformation is mainly driven by viscous flow in the lower crust. Such flow can transfer stress to the upper crust and load the rupture zone of the main shock at a decaying rate. Most aftershocks within the rupture zone, especially those that occurred after the first several weeks of the main shock, may have been triggered by continuous stress loading from viscous flow. The long-term decay time of aftershocks (about 2 years) approximately matches the decay of viscoelastic loading, and thus is controlled by the viscosity of the lower crust. Our model provides a physical interpretation of the observed correlation between aftershock decay rate and surface heat flow.Following the Mw 6.7 Northridge earthquake, significant postseismic displacements were resolved with GPS. Using a three-dimensional viscoelastic model, we suggest that this deformation is mainly driven by viscous flow in the lower crust. Such flow can transfer stress to the upper crust and load the rupture zone of the main shock at a decaying rate. Most aftershocks within the rupture zone, especially those that occurred after the first several weeks of the main shock, may have been triggered by continuous stress loading from viscous flow. The long-term decay time of aftershocks (about 2 years) approximately matches the decay of viscoelastic loading, and thus is controlled by the viscosity of the lower crust. Our model provides a physical interpretation of the observed correlation between aftershock decay rate and surface heat flow.

Fracture in Westerly granite under AE feedback and constant strain rate loading: Nucleation, quasi-static propagation, and the transition to unstable fracture propagation

USGS Publications Warehouse

Thompson, B.D.; Young, R.P.; Lockner, D.A.

2006-01-01

New observations of fracture nucleation are presented from three triaxial compression experiments on intact samples of Westerly granite, using Acoustic Emission (AE) monitoring. By conducting the tests under different loading conditions, the fracture process is demonstrated for quasi-static fracture (under AE Feedback load), a slowly developing unstable fracture (loaded at a 'slow' constant strain rate of 2.5 ?? 10-6/s) and an unstable fracture that develops near instantaneously (loaded at a 'fast' constant strain rate of 5 ?? 10-5/s). By recording a continuous ultrasonic waveform during the critical period of fracture, the entire AE catalogue can be captured and the exact time of fracture defined. Under constant strain loading, three stages are observed: (1) An initial nucleation or stable growth phase at a rate of ??? 1.3 mm/s, (2) a sudden increase to a constant or slowly accelerating propagation speed of ??? 18 mm/s, and (3) unstable, accelerating propagation. In the ??? 100 ms before rupture, the high level of AE activity (as seen on the continuous record) prevented the location of discrete AE events. A lower bound estimate of the average propagation velocity (using the time-to-rupture and the existing fracture length) suggests values of a few m/s. However from a low gain acoustic record, we infer that in the final few ms, the fracture propagation speed increased to 175 m/s. These results demonstrate similarities between fracture nucleation in intact rock and the nucleation of dynamic instabilities in stick slip experiments. It is suggested that the ability to constrain the size of an evolving fracture provides a crucial tool in further understanding the controls on fracture nucleation. ?? Birkha??user Verlag, Basel, 2006.

Real-time soft error rate measurements on bulk 40 nm SRAM memories: a five-year dual-site experiment

NASA Astrophysics Data System (ADS)

Autran, J. L.; Munteanu, D.; Moindjie, S.; Saad Saoud, T.; Gasiot, G.; Roche, P.

2016-11-01

This paper reports five years of real-time soft error rate experimentation conducted with the same setup at mountain altitude for three years and then at sea level for two years. More than 7 Gbit of SRAM memories manufactured in CMOS bulk 40 nm technology have been subjected to the natural radiation background. The intensity of the atmospheric neutron flux has been continuously measured on site during these experiments using dedicated neutron monitors. As the result, the neutron and alpha component of the soft error rate (SER) have been very accurately extracted from these measurements, refining the first SER estimations performed in 2012 for this SRAM technology. Data obtained at sea level evidence, for the first time, a possible correlation between the neutron flux changes induced by the daily atmospheric pressure variations and the measured SER. Finally, all of the experimental data are compared with results obtained from accelerated tests and numerical simulation.

Three-part joint modeling methods for complex functional data mixed with zero-and-one-inflated proportions and zero-inflated continuous outcomes with skewness.

PubMed

Li, Haocheng; Staudenmayer, John; Wang, Tianying; Keadle, Sarah Kozey; Carroll, Raymond J

2018-02-20

We take a functional data approach to longitudinal studies with complex bivariate outcomes. This work is motivated by data from a physical activity study that measured 2 responses over time in 5-minute intervals. One response is the proportion of time active in each interval, a continuous proportions with excess zeros and ones. The other response, energy expenditure rate in the interval, is a continuous variable with excess zeros and skewness. This outcome is complex because there are 3 possible activity patterns in each interval (inactive, partially active, and completely active), and those patterns, which are observed, induce both nonrandom and random associations between the responses. More specifically, the inactive pattern requires a zero value in both the proportion for active behavior and the energy expenditure rate; a partially active pattern means that the proportion of activity is strictly between zero and one and that the energy expenditure rate is greater than zero and likely to be moderate, and the completely active pattern means that the proportion of activity is exactly one, and the energy expenditure rate is greater than zero and likely to be higher. To address these challenges, we propose a 3-part functional data joint modeling approach. The first part is a continuation-ratio model to reorder the ordinal valued 3 activity patterns. The second part models the proportions when they are in interval (0,1). The last component specifies the skewed continuous energy expenditure rate with Box-Cox transformations when they are greater than zero. In this 3-part model, the regression structures are specified as smooth curves measured at various time points with random effects that have a correlation structure. The smoothed random curves for each variable are summarized using a few important principal components, and the association of the 3 longitudinal components is modeled through the association of the principal component scores. The difficulties in handling the ordinal and proportional variables are addressed using a quasi-likelihood type approximation. We develop an efficient algorithm to fit the model that also involves the selection of the number of principal components. The method is applied to physical activity data and is evaluated empirically by a simulation study. Copyright © 2017 John Wiley & Sons, Ltd.

Rheological Behavior and Microstructure of Ceramic Particulate/Aluminum Alloy Composites. Ph.D. Thesis Final Technical Report

NASA Technical Reports Server (NTRS)

Moon, Hee-Kyung

1990-01-01

The rheological behavior and microstructure were investigated using a concentric cylinder viscometer for three different slurries: semi-solid alloy slurries of a matrix alloy, Al-6.5wt percent Si: composite slurries, SiC (sub p) (8.5 microns)/Al-6.5wt percent Si, with the same matrix alloy in the molten state, and composite slurries of the same composition with the matrix alloy in the semi-solid state. The pseudoplasticity of these slurries was obtained by step changes of the shear rate from a given initial shear rate. To study the thixotropic behavior of the system, a slurry was allowed to rest for different periods of time, prior to shearing at a given initial shear rate. In the continuous cooling experiments, the viscosities of these slurries were dependent on the shear rate, cooling rate, volume fraction of the primary solid of the matrix alloy, and volume fraction of silicon carbide. In the isothermal experiments, all three kinds of slurries exhibited non-Newtonian behavior, depending on the volume fraction of solid particles.

Characterizing and minimizing the effects of noise in tide gauge time series: relative and geocentric sea level rise around Australia

NASA Astrophysics Data System (ADS)

Burgette, Reed J.; Watson, Christopher S.; Church, John A.; White, Neil J.; Tregoning, Paul; Coleman, Richard

2013-08-01

We quantify the rate of sea level rise around the Australian continent from an analysis of tide gauge and Global Positioning System (GPS) data sets. To estimate the underlying linear rates of sea level change in the presence of significant interannual and decadal variability (treated here as noise), we adopt and extend a novel network adjustment approach. We simultaneously estimate time-correlated noise as well as linear model parameters and realistic uncertainties from sea level time series at individual gauges, as well as from time-series differences computed between pairs of gauges. The noise content at individual gauges is consistent with a combination of white and time-correlated noise. We find that the noise in time series from the western coast of Australia is best described by a first-order Gauss-Markov model, whereas east coast stations generally exhibit lower levels of time-correlated noise that is better described by a power-law process. These findings suggest several decades of monthly tide gauge data are needed to reduce rate uncertainties to <0.5 mm yr-1 for undifferenced single site time series with typical noise characteristics. Our subsequent adjustment strategy exploits the more precise differential rates estimated from differenced time series from pairs of tide gauges to estimate rates among the network of 43 tide gauges that passed a stability analysis. We estimate relative sea level rates over three temporal windows (1900-2011, 1966-2011 and 1993-2011), accounting for covariance between time series. The resultant adjustment reduces the rate uncertainty across individual gauges, and partially mitigates the need for century-scale time series at all sites in the network. Our adjustment reveals a spatially coherent pattern of sea level rise around the coastline, with the highest rates in northern Australia. Over the time periods beginning in 1900, 1966 and 1993, we find weighted average rates of sea level rise of 1.4 ± 0.6, 1.7 ± 0.6 and 4.6 ± 0.8 mm yr-1, respectively. While the temporal pattern of the rate estimates is consistent with acceleration in sea level rise, it may not be significant, as the uncertainties for the shorter analysis periods may not capture the full range of temporal variation. Analysis of the available continuous GPS records that have been collected within 80 km of Australian tide gauges suggests that rates of vertical crustal motion are generally low, with the majority of sites showing motion statistically insignificant from zero. A notable exception is the significant component of vertical land motion that contributes to the rapid rate of relative sea level change (>4 mm yr-1) at the Hillarys site in the Perth area. This corresponds to crustal subsidence that we estimate in our GPS analysis at a rate of -3.1 ± 0.7 mm yr-1, and appears linked to groundwater withdrawal. Uncertainties on the rates of vertical displacement at GPS sites collected over a decade are similar to what we measure in several decades of tide gauge data. Our results motivate continued observations of relative sea level using tide gauges, maintained with high-accuracy terrestrial and continuous co-located satellite-based surveying.

A seamless acquisition digital storage oscilloscope with three-dimensional waveform display

NASA Astrophysics Data System (ADS)

Yang, Kuojun; Tian, Shulin; Zeng, Hao; Qiu, Lei; Guo, Lianping

2014-04-01

In traditional digital storage oscilloscope (DSO), sampled data need to be processed after each acquisition. During data processing, the acquisition is stopped and oscilloscope is blind to the input signal. Thus, this duration is called dead time. With the rapid development of modern electronic systems, the effect of infrequent events becomes significant. To capture these occasional events in shorter time, dead time in traditional DSO that causes the loss of measured signal needs to be reduced or even eliminated. In this paper, a seamless acquisition oscilloscope without dead time is proposed. In this oscilloscope, three-dimensional waveform mapping (TWM) technique, which converts sampled data to displayed waveform, is proposed. With this technique, not only the process speed is improved, but also the probability information of waveform is displayed with different brightness. Thus, a three-dimensional waveform is shown to the user. To reduce processing time further, parallel TWM which processes several sampled points simultaneously, and dual-port random access memory based pipelining technique which can process one sampling point in one clock period are proposed. Furthermore, two DDR3 (Double-Data-Rate Three Synchronous Dynamic Random Access Memory) are used for storing sampled data alternately, thus the acquisition can continue during data processing. Therefore, the dead time of DSO is eliminated. In addition, a double-pulse test method is adopted to test the waveform capturing rate (WCR) of the oscilloscope and a combined pulse test method is employed to evaluate the oscilloscope's capture ability comprehensively. The experiment results show that the WCR of the designed oscilloscope is 6 250 000 wfms/s (waveforms per second), the highest value in all existing oscilloscopes. The testing results also prove that there is no dead time in our oscilloscope, thus realizing the seamless acquisition.

A seamless acquisition digital storage oscilloscope with three-dimensional waveform display

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

Yang, Kuojun, E-mail: kuojunyang@gmail.com; Guo, Lianping; School of Electrical and Electronic Engineering, Nanyang Technological University

In traditional digital storage oscilloscope (DSO), sampled data need to be processed after each acquisition. During data processing, the acquisition is stopped and oscilloscope is blind to the input signal. Thus, this duration is called dead time. With the rapid development of modern electronic systems, the effect of infrequent events becomes significant. To capture these occasional events in shorter time, dead time in traditional DSO that causes the loss of measured signal needs to be reduced or even eliminated. In this paper, a seamless acquisition oscilloscope without dead time is proposed. In this oscilloscope, three-dimensional waveform mapping (TWM) technique, whichmore » converts sampled data to displayed waveform, is proposed. With this technique, not only the process speed is improved, but also the probability information of waveform is displayed with different brightness. Thus, a three-dimensional waveform is shown to the user. To reduce processing time further, parallel TWM which processes several sampled points simultaneously, and dual-port random access memory based pipelining technique which can process one sampling point in one clock period are proposed. Furthermore, two DDR3 (Double-Data-Rate Three Synchronous Dynamic Random Access Memory) are used for storing sampled data alternately, thus the acquisition can continue during data processing. Therefore, the dead time of DSO is eliminated. In addition, a double-pulse test method is adopted to test the waveform capturing rate (WCR) of the oscilloscope and a combined pulse test method is employed to evaluate the oscilloscope's capture ability comprehensively. The experiment results show that the WCR of the designed oscilloscope is 6 250 000 wfms/s (waveforms per second), the highest value in all existing oscilloscopes. The testing results also prove that there is no dead time in our oscilloscope, thus realizing the seamless acquisition.« less

Quantifying in-stream nitrate reaction rates using continuously-collected water quality data

Treesearch

Matthew Miller; Anthony Tesoriero; Paul Capel

2016-01-01

High frequency in situ nitrate data from three streams of varying hydrologic condition, land use, and watershed size were used to quantify the mass loading of nitrate to streams from two sources – groundwater discharge and event flow – at a daily time step for one year. These estimated loadings were used to quantify temporally-variable in-stream nitrate processing ...

Building a Morbidostat: An automated continuous-culture device for studying bacterial drug resistance under dynamically sustained drug inhibition

PubMed Central

Toprak, Erdal; Veres, Adrian; Yildiz, Sadik; Pedraza, Juan M.; Chait, Remy; Paulsson, Johan; Kishony, Roy

2013-01-01

We present a protocol for building and operating an automated fluidic system for continuous culture that we call the “morbidostat”. The morbidostat is used to follow evolution of microbial drug resistance in real time. Instead of exposing bacteria to predetermined drug environments, the morbidostat constantly measures the growth rates of evolving microbial populations and dynamically adjusts drug concentrations inside culture vials in order to maintain a constant drug induced inhibition. The growth rate measurements are done using an optical detection system that is based on measuring the intensity of back-scattered light from bacterial cells suspended in the liquid culture. The morbidostat can additionally be used as a chemostat or a turbidostat. The whole system can be built from readily available components within two to three weeks, by biologists with some electronics experience or engineers familiar with basic microbiology. PMID:23429717

A multiparameter wearable physiologic monitoring system for space and terrestrial applications

NASA Technical Reports Server (NTRS)

Mundt, Carsten W.; Montgomery, Kevin N.; Udoh, Usen E.; Barker, Valerie N.; Thonier, Guillaume C.; Tellier, Arnaud M.; Ricks, Robert D.; Darling, Robert B.; Cagle, Yvonne D.; Cabrol, Nathalie A.;

Effect of centrifugal fractionation protocols on quality and recovery rate of equine sperm.

PubMed

Edmond, A J; Brinsko, S P; Love, C C; Blanchard, T L; Teague, S R; Varner, D D

2012-03-15

Centrifugal fractionation of semen is commonly done to improve quality of human semen in assisted-reproduction laboratories, allowing sperm separation based on their isopycnic points. Sperm with morphologic abnormalities are often more buoyant, promoting their retention above defined density media, with structurally normal sperm passing through the media following centrifugation. Three experiments were conducted to evaluate the effects of density-medium type, centrifuge-tube size, sperm number, and density-medium volume (column height) on stallion sperm quality and recovery rate in sperm pellets following centrifugation. In all three experiments, equine semen was initially centrifuged to increase sperm concentration. In Experiment 1, semen was layered over continuous or discontinuous gradients. For Experiment 2, semen was layered over three column heights of continuous gradients in 15- or 50-ml conical-bottom tubes. For Experiment 3, increasing sperm numbers were layered over continuous gradient in 15- or 50-ml conical-bottom tubes. Following centrifugation, sperm pellets were evaluated for sperm morphologic quality, motility, DNA integrity, and recovery rate. Centrifugal fractionation improved (P < 0.05) sperm morphology, motility, and DNA integrity, as compared to controls. The continuous gradient increased (P < 0.05) sperm recovery rate relative to the discontinuous gradient, whereas sperm processed in 15-ml tubes yielded higher velocity and higher recovery rates (P < 0.05 for each) than that processed in 50-ml tubes. Sperm recovery rate was not affected (P > 0.05) by column height of gradient. Increasing sperm number subjected to gradient centrifugation decreased (P < 0.05) sperm recovery rate when 15-ml tubes were used. Copyright © 2012 Elsevier Inc. All rights reserved.

A randomised controlled trial comparing three analgesia regimens following total knee joint replacement: continuous femoral nerve block, intrathecal morphine or both.

PubMed

Olive, D J; Barrington, M J; Simone, S A; Kluger, R

2015-07-01

This randomised controlled trial compared three analgesia regimens following primary unilateral total knee joint replacement: continuous femoral nerve block (CFNB), intrathecal morphine (ITM), and both. The primary outcome was pain ratings over the first 24 hours. Secondary outcomes included morphine consumption, nausea, pruritus and sedation ratings, oxygen saturation (SpO2) ratings, and ability to mobilise postoperatively. All patients received a spinal anaesthetic and a postoperative patient-controlled morphine pump. Patients were randomised to receive CFNB, ITM, or both. In patients with no CFNB, the use of ITM was blinded. Eighty-one patients were randomised and there were no withdrawals. At 24 hours, the ITM-only group had higher pain ratings than either of the other groups (P=0.04 versus CFNB, P=0.01 versus combination). In the 18 to 24 hour period, the ITM group used more morphine than either of the other groups. There were no statistically significant differences in pain ratings or morphine consumption at earlier time intervals. The ITM group were less likely to be able to sit out of bed on day one. Patients who received ITM were more likely to have pruritus. There were no statistically significant differences in nausea, SpO₂or sedation ratings. This study showed that a CFNB resulted in reduced pain and was also associated with less morphine consumption and improved mobilisation at 24 hours compared to ITM. This study did not show any statistically significant differences between CFNB alone and CFNB+ITM.

Randomised controlled trial using smartphone website vs leaflet to support antenatal perineal massage practice for pregnant women.

PubMed

Takeuchi, Shoko; Horiuchi, Shigeko

2016-10-01

In Japan, the rate of pregnant women who practice antenatal perineal massage was only 15.1%. The aim of this study was to develop and evaluate a smartphone website and a leaflet to support antenatal perineal massage practice for primiparous women. In a randomised control trial, 161 primiparous women were randomly assigned to a smartphone website group (n=81) or a leaflet group (n=80). Data analysis were by per protocol analysis and intention to treat analysis. Of the 161 women participants, 47 in the smartphone website group and 49 in the leaflet group completed all questionnaires. Primary outcome was continuance rate (three times a week over a three week period) of antenatal perineal massage practice. The rates by a per protocol analysis were 51.1% in the smartphone website group and 51.0% in the leaflet group, respectively. There was no significant difference between the groups. Moreover, the rates by an intention to treat analysis were 29.6% in the smartphone website group and 31.3% in the leaflet group, respectively. There was also no significant difference between the groups. There were no significant differences in the evaluation of perineal massage, childbirth self-efficacy, satisfaction with efforts towards childbirth, and perineal outcomes following childbirth which were measured as secondary outcomes between the groups. There was no significant difference in continuance rate of antenatal perineal massage practice between those using a smartphone website and those with a leaflet, however, the rate was better than no instructions. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Evaluation of continuous oxydesulfurization processes. Final technical report, September 1979-July 1981

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

Jones, J.F.; Wever, D.M.

1981-07-01

Three processes developed by Pittsburgh Energy Technology Center (PETC), Ledgemont Laboratories, and Ames Laboratories for the oxydesulfurization of coal were evaluated in continuous processing equipment designed, built, and/or adapted for the purpose at the DOE-owned Multi-Use Fuels and Energy Processes Test Plant (MEP) located at TRW's Capistrano Test Site in California. The three processes differed primarily in the chemical additives (none, sodium carbonate, or ammonia), fed to the 20% to 40% coal/water slurries, and in the oxygen content of the feed gas stream. Temperature, pressure, residence time, flow rates, slurry concentration and stirrer speed were the other primary independent variables.more » The amount of organic sulfur removed, total sulfur removed and the Btu recovery were the primary dependent variables. Evaluation of the data presented was not part of the test effort.« less

Study of seasonal and long-term vertical deformation in Nepal based on GPS and GRACE observations

NASA Astrophysics Data System (ADS)

Zhang, Tengxu; Shen, WenBin; Pan, Yuanjin; Luan, Wei

2018-02-01

Lithospheric deformation signal can be detected by combining data from continuous global positioning system (CGPS) and satellite observations from the Gravity Recovery and Climate Experiment (GRACE). In this paper, we use 2.5- to 19-year-long time series from 35 CGPS stations to estimate vertical deformation rates in Nepal, which is located in the southern side of the Himalaya. GPS results were compared with GRACE observations. Principal component analysis was conducted to decompose the time series into three-dimensional principal components (PCs) and spatial eigenvectors. The top three high-order PCs were calculated to correct common mode errors. Both GPS and GRACE observations showed significant seasonal variations. The observed seasonal GPS vertical variations are in good agreement with those from the GRACE-derived results, particularly for changes in surface pressure, non-tidal oceanic mass loading, and hydrologic loading. The GPS-observed rates of vertical deformation obtained for the region suggest both tectonic impact and mass decrease. The rates of vertical crustal deformation were estimated by removing the GRACE-derived hydrological vertical rates from the GPS measurements. Most of the sites located in the southern part of the Main Himalayan Thrust subsided, whereas the northern part mostly showed an uplift. These results may contribute to the understanding of secular vertical crustal deformation in Nepal.

Analysis of temperature profiles for investigating stream losses beneath ephemeral channels

USGS Publications Warehouse

Constantz, Jim; Stewart, Amy E.; Niswonger, Richard G.; Sarma, Lisa

2002-01-01

Continuous estimates of streamflow are challenging in ephemeral channels. The extremely transient nature of ephemeral streamflows results in shifting channel geometry and degradation in the calibration of streamflow stations. Earlier work suggests that analysis of streambed temperature profiles is a promising technique for estimating streamflow patterns in ephemeral channels. The present work provides a detailed examination of the basis for using heat as a tracer of stream/groundwater exchanges, followed by a description of an appropriate heat and water transport simulation code for ephemeral channels, as well as discussion of several types of temperature analysis techniques to determine streambed percolation rates. Temperature‐based percolation rates for three ephemeral stream sites are compared with available surface water estimates of channel loss for these sites. These results are combined with published results to develop conclusions regarding the accuracy of using vertical temperature profiles in estimating channel losses. Comparisons of temperature‐based streambed percolation rates with surface water‐based channel losses indicate that percolation rates represented 30% to 50% of the total channel loss. The difference is reasonable since channel losses include both vertical and nonvertical component of channel loss as well as potential evapotranspiration losses. The most significant advantage of the use of sediment‐temperature profiles is their robust and continuous nature, leading to a long‐term record of the timing and duration of channel losses and continuous estimates of streambed percolation. The primary disadvantage is that temperature profiles represent the continuous percolation rate at a single point in an ephemeral channel rather than an average seepage loss from the entire channel.

Prospective randomized controlled study of interferon-alpha in preventing hepatocellular carcinoma recurrence after medical ablation therapy for primary tumors.

PubMed

Lin, Shi-Ming; Lin, Chun-Jung; Hsu, Chao-Wei; Tai, Dar-In; Sheen, I-Shyan; Lin, Deng-Yn; Liaw, Yun-Fan

2004-01-15

Hepatocellular carcinoma (HCC) recurrence after ablation therapy for primary tumors is common. To evaluate the effectiveness of interferon-alpha (IFN-alpha) in preventing HCC recurrence, 30 eligible patients were randomized into three groups: 11 patients treated with three mega units (MU) of IFN-alpha three times weekly for 24 months (IFN-alpha-continuous group), 9 patients treated with 3 MU of IFN-alpha daily for 10 days every month for 6 months followed by 3 MU of IFN-alpha daily for 10 days every 3 months for a further 18 months (IFN-alpha-intermittent group), and 10 patients who received no IFN-alpha therapy (control group). The three groups were comparable in terms of etiology, demographics, and laboratory data at entry and HCC characteristics. After a median follow-up of 27 months (range 4-53 months), 9 patients (90%) in the control group and 9 patients (45%) in 2 treatment groups (6 patients in the IFN-alpha-continuous group and 3 patients in the IFN-alpha-intermittent group) developed an HCC recurrence (P = 0.021). Cumulative HCC recurrence rates in the IFN-alpha-intermittent, IFN-alpha-continuous, and control groups were 22.2%, 27.3%, and 40% at the end of 1 year and 33.3%, 54.6%, and 90% at the end of 4 years (P = 0.0375), respectively (control vs. IFN-alpha-intermittent group, P = 0.0123; vs. IFN-alpha-continuous group, P = 0.0822). If both IFN-alpha groups were combined, the cumulative HCC recurrence rate of the patients treated with IFN-alpha and the control group was 25% and 40% at the end of 1 year and 47% and 90% at the end of 4 years, respectively (P = 0.0135). The data suggested that IFN-alpha therapy may reduce HCC recurrence after medical ablation therapy for primary tumors. Copyright 2003 American Cancer Society.

GPS Imaging suggests links between climate, magmatism, seismicity, and tectonics in the Sierra Nevada-Long Valley Caldera-Walker Lane system, western United States

NASA Astrophysics Data System (ADS)

Hammond, W. C.; Blewitt, G.; Kreemer, C.; Smith, K.

2017-12-01

The Walker Lane is a region of complex active crustal transtension in the western Great Basin of the western United States, accommodating about 20% of the 50 mm/yr relative motion between the Pacific and North American plates. The Long Valley caldera lies in the central Walker Lane in eastern California, adjacent to the eastern boundary of the Sierra Nevada/Great Valley microplate, and experiences intermittent inflation, uplift, and volcanic unrest from the magma chamber that resides at middle crustal depths. Normal and transform faults accommodating regional tectonic transtension pass by and through the caldera, complicating the interpretation of the GPS-measured strain rate field, estimates of fault slip rates, and seismic hazard. Several dozen continuously recording GPS stations measure strain and uplift in the area with mm precision. They observe that the most recent episode of uplift at Long Valley began in mid-2011, continuing until late 2016, raising the surface by 100 mm in 6 years. The timing of the initiation of uplift coincides with the beginning of severe drought in California. Furthermore, the timing of a recent pause in uplift coincides with the very wet 2016-2017 winter, which saw approximately double normal snow pack. In prior studies, we showed that the timing of changes in geodetically measured uplift rate of the Sierra Nevada coincides with the timing of drought conditions in California, suggesting a link between hydrological loading and Sierra Nevada elevation. Here we take the analysis three steps further to show that changes in Sierra Nevada uplift rate coincide in time with 1) enhanced inflation at the Long Valley caldera, 2) shifts in the patterns and rates of horizontal tensor strain rate, and 3) seismicity patterns in the central Walker Lane. We use GPS solutions from the Nevada Geodetic Laboratory and the new GPS Imaging technique to produce robust animations of the time variable strain and uplift fields. The goals of this work are to document links between climate, Sierra Nevada uplift rates, response of the magmatic system, and seismicity in the Central Walker Lane, and to explore the physical mechanisms that may be behind these correlations.

Sampling trace organic compounds in water: a comparison of a continuous active sampler to continuous passive and discrete sampling methods

USGS Publications Warehouse

Coes, Alissa L.; Paretti, Nicholas V.; Foreman, William T.; Iverson, Jana L.; Alvarez, David A.

2014-01-01

A continuous active sampling method was compared to continuous passive and discrete sampling methods for the sampling of trace organic compounds (TOCs) in water. Results from each method are compared and contrasted in order to provide information for future investigators to use while selecting appropriate sampling methods for their research. The continuous low-level aquatic monitoring (CLAM) sampler (C.I.Agent® Storm-Water Solutions) is a submersible, low flow-rate sampler, that continuously draws water through solid-phase extraction media. CLAM samplers were deployed at two wastewater-dominated stream field sites in conjunction with the deployment of polar organic chemical integrative samplers (POCIS) and the collection of discrete (grab) water samples. All samples were analyzed for a suite of 69 TOCs. The CLAM and POCIS samples represent time-integrated samples that accumulate the TOCs present in the water over the deployment period (19–23 h for CLAM and 29 days for POCIS); the discrete samples represent only the TOCs present in the water at the time and place of sampling. Non-metric multi-dimensional scaling and cluster analysis were used to examine patterns in both TOC detections and relative concentrations between the three sampling methods. A greater number of TOCs were detected in the CLAM samples than in corresponding discrete and POCIS samples, but TOC concentrations in the CLAM samples were significantly lower than in the discrete and (or) POCIS samples. Thirteen TOCs of varying polarity were detected by all of the three methods. TOC detections and concentrations obtained by the three sampling methods, however, are dependent on multiple factors. This study found that stream discharge, constituent loading, and compound type all affected TOC concentrations detected by each method. In addition, TOC detections and concentrations were affected by the reporting limits, bias, recovery, and performance of each method.

Sampling trace organic compounds in water: a comparison of a continuous active sampler to continuous passive and discrete sampling methods.

PubMed

Coes, Alissa L; Paretti, Nicholas V; Foreman, William T; Iverson, Jana L; Alvarez, David A

2014-03-01

A continuous active sampling method was compared to continuous passive and discrete sampling methods for the sampling of trace organic compounds (TOCs) in water. Results from each method are compared and contrasted in order to provide information for future investigators to use while selecting appropriate sampling methods for their research. The continuous low-level aquatic monitoring (CLAM) sampler (C.I.Agent® Storm-Water Solutions) is a submersible, low flow-rate sampler, that continuously draws water through solid-phase extraction media. CLAM samplers were deployed at two wastewater-dominated stream field sites in conjunction with the deployment of polar organic chemical integrative samplers (POCIS) and the collection of discrete (grab) water samples. All samples were analyzed for a suite of 69 TOCs. The CLAM and POCIS samples represent time-integrated samples that accumulate the TOCs present in the water over the deployment period (19-23 h for CLAM and 29 days for POCIS); the discrete samples represent only the TOCs present in the water at the time and place of sampling. Non-metric multi-dimensional scaling and cluster analysis were used to examine patterns in both TOC detections and relative concentrations between the three sampling methods. A greater number of TOCs were detected in the CLAM samples than in corresponding discrete and POCIS samples, but TOC concentrations in the CLAM samples were significantly lower than in the discrete and (or) POCIS samples. Thirteen TOCs of varying polarity were detected by all of the three methods. TOC detections and concentrations obtained by the three sampling methods, however, are dependent on multiple factors. This study found that stream discharge, constituent loading, and compound type all affected TOC concentrations detected by each method. In addition, TOC detections and concentrations were affected by the reporting limits, bias, recovery, and performance of each method. Published by Elsevier B.V.

Monitoring unrest in a large silicic caldera, the long Valley-inyo craters volcanic complex in east-central California

USGS Publications Warehouse

Hill, D.P.

1984-01-01

Recent patterns of geologic unrest in long Valley caldera in east-central California emphasize that this large, silicic volcanic system and the adjacent, geologically youthful Inyo-Mono Craters volcanic chain are still active and capable of producing locally hazardous volcanic eruptions. A series of four magnitude -6 earthquakes in May 1980 called attention to this current episode of unrest, and subsequent activity has included numerous earthquake swarms in the south moat of the caldera accompanied by inflation of the resurgent dome by more than 50 cm over the last five years. The seismicity associated with this unrest is currently monitored by a network of 31 telemetered seismic stations with an automatic processing system that yelds hypocentral locations and earthquake magnitudes in near-real time. Deformation of the ground is monitored by a) a series of overlapping trilateration networks that provide coverage ranging from annual measurements of regional deformation to daily measurements of deformation local to the active, southern section of the caldera, b) a regional network of level lines surveyed annually, c) a regional network of precise gravity stations occupied annually, d) local, L-shaped level figures surveyed every few months, and e) a network of fourteen borehole tiltmeter clusters (two instruments in each cluster) and a borehole dilatometer, the telemetered signals from which provide continuous data on deformation rates. Additional telemetered data provide continuous information on fluctuations in the local magnetic field, hydrogen gas emission rates at three sites, and water level and temperatures in three wells. Continuous data on disharge rates and temperatures from hot springs and fumaroles are collected by several on-site recorders within the caldera, and samples for liquid and gas chemistry are collected several times per year from selected hot springs and fumaroles. ?? 1984 Intern. Association of Volcanology and Chemistry of the Earth's Interior.

The Spectrum of Mathematical Models.

ERIC Educational Resources Information Center

Karplus, Walter J.

1983-01-01

Mathematical modeling problems encountered in many disciplines are discussed in terms of the modeling process and applications of models. The models are classified according to three types of abstraction: continuous-space-continuous-time, discrete-space-continuous-time, and discrete-space-discrete-time. Limitations in different kinds of modeling…

Discontinuous and continuous hardening processes in calcium and calcium—tin micro-alloyed lead: influence of 'secondary-lead' impurities

NASA Astrophysics Data System (ADS)

Bouirden, L.; Hilger, J. P.; Hertz, J.

Different transformations in leadcalcium and leadcaciumtin alloys are observed with various complementary techniques such as anisothermal microcalorimetry, optical and electronic microscopy, hardness measurements. Three alloy states are studied: as-cast, rehomogenised/water-quenched, rehomogenised/air-cooled. With binary leadcalcium alloys, three successive discontinuous transformations are observed, namely: an initial and complete discontinuous transformation with regular moving of the front of reaction; a second and incomplete discontinuous transformation (puzzle-shaped); a third and incomplete discontinuous transformation with precipitation of Pb 3Ca. The role of secondary-lead impurities is complex: Ag reduces and Bi accelerates the rate of the discontinuous reaction, while Al refines the grain size. Leadcalciumtin are characterized by the Sn/Ca ratio. For very small values of this ratio, the hardening is similar to that of leadcalcium alloys. For high ratio values, the hardening takes place after an incubation period and proceeds via a continuous micro-precipitation of the (PbSn) 3Ca Compound. For intermediate ratios, the different processes are able to operate separately in sequence. Ag increases the rate of the continuous precipitation and reduces the incubation time. No significant effects are observed with Bi or Al. The kinetic laws of the different transformations are presented and values for the energy of activation are determined.

Slow slip events in Guerrero, Mexico, and consequences on strain accumulation over the past 15 years.

NASA Astrophysics Data System (ADS)

Radiguet, M.; Cotton, F.; Cavalié, O.; Pathier, E.; Kostoglodov, V.; Vergnolle, M.; Campillo, M.; Walpersdorf, A.; Cotte, N.; Santiago, J.; Franco, S.

2012-12-01

Continuous Global Positioning System (cGPS) time series in Guerrero, Mexico, reveal the widespread existence of large Slow Slip Events (SSEs) at the boundary between the Cocos and North American plates. The existence of these SSEs asks the question of how seismic and aseismic slips complement each other in subduction zones. We examined the last three SSEs that occurred in 2001/2002, 2006 and 2009/2010, and their impact on the strain accumulation along the Guerrero subduction margin. We use continuous cGPS time series and InSAR images to evaluate the surface displacement during SSEs and inter-SSE periods. The slip distributions on the plate interface associated with each SSE, as well as the inter-SSE (short-term) coupling rates are evaluated by inverting these surface displacements. Our results reveal that the three analyzed SSEs have equivalent moment magnitudes of around 7.5 and their lateral extension is variable.The slip distributions for the three SSEs show that in the Guerrero gap area, the slow slip occurs at shallower depth (updip limit around 15-20 km) than in surrounding regions. The InSAR data provide additional information for the 2006 SSE. The joint inversion of InSAR and cGPS data confirms the lateral variation of the slip distribution along the trench, with shallower slip in the Guerrero seismic gap, west of Acapulco, and deeper slip further east. Inversion of inter-SSE displacement rates reveal that during the inter-SSE time intervals, the interplate coupling is high in the area where the slow slip subsequently occurs. Over a 12 year period, corresponding to three cycles of SSEs, our results reveal that the accumulated slip deficit in the Guerrero gap area is only ¼ of the slip deficit accumulated on both sides of the gap. Moreover, the regions of large slip deficit coincide with the rupture areas of recent large earthquakes. We conclude that the SSEs account for a major portion of the overall moment release budget in the Guerrero gap. If large subduction thrust earthquakes occur in the Guerrero gap, their recurrence time is probably increased compared to adjacent regions.

One and three doses of propranolol a day in hypertension.

PubMed

van den Brink, G; Boer, P; van Asten, P; Dorhout Mees, E J; Geyskes, G G

1980-01-01

In 26 patients with essential hypertension who were on continuous chlorthalidone therapy, 1 and 3 daily doses of propranolol were compared in a crossover study. Plasma propranolol levels and heart rates had larger daily fluctuations on single-dose therapy than on 3 times daily; plasma renin activity was more constant. There was no significant difference in blood pressures. Once-daily propranolol dosage was well tolerated and possibly gave less rise to the troublesome side effect of vivid dreaming.

Temporal variability in stage-discharge relationships

NASA Astrophysics Data System (ADS)

Guerrero, José-Luis; Westerberg, Ida K.; Halldin, Sven; Xu, Chong-Yu; Lundin, Lars-Christer

2012-06-01

SummaryAlthough discharge estimations are central for water management and hydropower, there are few studies on the variability and uncertainty of their basis; deriving discharge from stage heights through the use of a rating curve that depends on riverbed geometry. A large fraction of the world's river-discharge stations are presumably located in alluvial channels where riverbed characteristics may change over time because of erosion and sedimentation. This study was conducted to analyse and quantify the dynamic relationship between stage and discharge and to determine to what degree currently used methods are able to account for such variability. The study was carried out for six hydrometric stations in the upper Choluteca River basin, Honduras, where a set of unusually frequent stage-discharge data are available. The temporal variability and the uncertainty of the rating curve and its parameters were analysed through a Monte Carlo (MC) analysis on a moving window of data using the Generalised Likelihood Uncertainty Estimation (GLUE) methodology. Acceptable ranges for the values of the rating-curve parameters were determined from riverbed surveys at the six stations, and the sampling space was constrained according to those ranges, using three-dimensional alpha shapes. Temporal variability was analysed in three ways: (i) with annually updated rating curves (simulating Honduran practices), (ii) a rating curve for each time window, and (iii) a smoothed, continuous dynamic rating curve derived from the MC analysis. The temporal variability of the rating parameters translated into a high rating-curve variability. The variability could turn out as increasing or decreasing trends and/or cyclic behaviour. There was a tendency at all stations to a seasonal variability. The discharge at a given stage could vary by a factor of two or more. The quotient in discharge volumes estimated from dynamic and static rating curves varied between 0.5 and 1.5. The difference between discharge volumes derived from static and dynamic curves was largest for sub-daily ratings but stayed large also for monthly and yearly totals. The relative uncertainty was largest for low flows but it was considerable also for intermediate and large flows. The standard procedure of adjusting rating curves when calculated and observed discharge differ by more than 5% would have required continuously updated rating curves at the studied locations. We believe that these findings can be applicable to many other discharge stations around the globe.

A multiscale MDCT image-based breathing lung model with time-varying regional ventilation

PubMed Central

Yin, Youbing; Choi, Jiwoong; Hoffman, Eric A.; Tawhai, Merryn H.; Lin, Ching-Long

2012-01-01

A novel algorithm is presented that links local structural variables (regional ventilation and deforming central airways) to global function (total lung volume) in the lung over three imaged lung volumes, to derive a breathing lung model for computational fluid dynamics simulation. The algorithm constitutes the core of an integrative, image-based computational framework for subject-specific simulation of the breathing lung. For the first time, the algorithm is applied to three multi-detector row computed tomography (MDCT) volumetric lung images of the same individual. A key technique in linking global and local variables over multiple images is an in-house mass-preserving image registration method. Throughout breathing cycles, cubic interpolation is employed to ensure C1 continuity in constructing time-varying regional ventilation at the whole lung level, flow rate fractions exiting the terminal airways, and airway deformation. The imaged exit airway flow rate fractions are derived from regional ventilation with the aid of a three-dimensional (3D) and one-dimensional (1D) coupled airway tree that connects the airways to the alveolar tissue. An in-house parallel large-eddy simulation (LES) technique is adopted to capture turbulent-transitional-laminar flows in both normal and deep breathing conditions. The results obtained by the proposed algorithm when using three lung volume images are compared with those using only one or two volume images. The three-volume-based lung model produces physiologically-consistent time-varying pressure and ventilation distribution. The one-volume-based lung model under-predicts pressure drop and yields un-physiological lobar ventilation. The two-volume-based model can account for airway deformation and non-uniform regional ventilation to some extent, but does not capture the non-linear features of the lung. PMID:23794749

Pre-school children with and without developmental delay: behaviour problems and parenting stress over time.

PubMed

Baker, B L; McIntyre, L L; Blacher, J; Crnic, K; Edelbrock, C; Low, C

2003-01-01

Children with intellectual disability are at heightened risk for behaviour problems and diagnosed mental disorder. The present authors studied the early manifestation and continuity of problem behaviours in 205 pre-school children with and without developmental delays. Behaviour problems were quite stable over the year from age 36-48 months. Children with developmental delays were rated higher on behaviour problems than their non-delayed peers, and were three times as likely to score in the clinical range. Mothers and fathers showed high agreement in their rating of child problems, especially in the delayed group. Parenting stress was also higher in the delayed group, but was related to the extent of behaviour problems rather than to the child's developmental delay. Over time, a transactional model fit the relationship between parenting stress and behaviour problems: high parenting stress contributed to a worsening in child behaviour problems over time, and high child behaviour problems contributed to a worsening in parenting stress. Findings for mothers and fathers were quite similar.

Effects of hemoperfusion and continuous renal replacement therapy on patient survival following paraquat poisoning.

PubMed

Wang, Yadong; Chen, Yao; Mao, Lu; Zhao, Guangju; Hong, Guangliang; Li, Mengfang; Wu, Bin; Chen, Xiaorong; Tan, Meng; Wang, Na; Lu, Zhongqiu

2017-01-01

Mortality in patients with paraquat (PQ) poisoning is related to plasma PQ levels. Concentrations lower than 5,000 ng/mL are considered critical but curable. This study assessed the effects of hemoperfusion (HP) and continuous renal replacement therapy (CRRT) on the survival of PQ-poisoned patients with plasma PQ levels below 5,000ng/mL. We analyzed the records of 164 patients with PQ poisoning who were treated at the First Affiliated Hospital of Wenzhou Medical University in China between January 2011 and May 2015. We divided these patients into six sub-groups based on baseline plasma PQ levels and treatment, compared their clinical characteristics, and analyzed their survival rates. Patient sub-groups did not differ in terms of age, sex, time between poisoning and hospital admission, or time to first gavage. Biochemical indicators improved over time in all sub-groups following treatment, and the combined HP and CRRT treatment yielded better results than HP or CRRT alone. Fatality rates in the three treatment sub-groups did not differ among patients with baseline plasma PQ levels of 50-1,000 ng/mL, but in patients with 1,000-5,000 ng/mL levels, the mortality rate was 59.2% (HP treatment group), 48% (CRRT treatment group), and 37.9% (combined treatment group). Mortality rates were higher 10-30 days after hospitalization than in the first 10 days after admission. In the early stages of PQ poisoning, CRRT is effective in reducing patient fatality rates, particularly when combined with HP. Our data could be useful in increasing survival in acute PQ poisoning patients.

Age-related decline in ovarian follicle stocks differ between chimpanzees (Pan troglodytes) and humans.

PubMed

Cloutier, Christina T; Coxworth, James E; Hawkes, Kristen

2015-02-01

Similarity in oldest parturitions in humans and great apes suggests that we maintain ancestral rates of ovarian aging. Consistent with that hypothesis, previous counts of primordial follicles in postmortem ovarian sections from chimpanzees (Pan troglodytes) showed follicle stock decline at the same rate that human stocks decline across the same ages. Here, we correct that finding with a chimpanzee sample more than three times larger than the previous one, which also allows comparison into older ages. Analyses show depletion rates similar until about age 35, but after 35, the human counts continue to fall with age, while the change is much less steep in chimpanzees. This difference implicates likely effects on ovarian dynamics from other physiological systems that are senescing at different rates, and, potentially, different perimenopausal experience for chimpanzees and humans.

Detection of Coronal Mass Ejections Using Multiple Features and Space-Time Continuity

NASA Astrophysics Data System (ADS)

Zhang, Ling; Yin, Jian-qin; Lin, Jia-ben; Feng, Zhi-quan; Zhou, Jin

2017-07-01

Coronal Mass Ejections (CMEs) release tremendous amounts of energy in the solar system, which has an impact on satellites, power facilities and wireless transmission. To effectively detect a CME in Large Angle Spectrometric Coronagraph (LASCO) C2 images, we propose a novel algorithm to locate the suspected CME regions, using the Extreme Learning Machine (ELM) method and taking into account the features of the grayscale and the texture. Furthermore, space-time continuity is used in the detection algorithm to exclude the false CME regions. The algorithm includes three steps: i) define the feature vector which contains textural and grayscale features of a running difference image; ii) design the detection algorithm based on the ELM method according to the feature vector; iii) improve the detection accuracy rate by using the decision rule of the space-time continuum. Experimental results show the efficiency and the superiority of the proposed algorithm in the detection of CMEs compared with other traditional methods. In addition, our algorithm is insensitive to most noise.

Three dimensional modelling of earthquake rupture cycles on frictional faults

NASA Astrophysics Data System (ADS)

Simpson, Guy; May, Dave

2017-04-01

We are developing an efficient MPI-parallel numerical method to simulate earthquake sequences on preexisting faults embedding within a three dimensional viscoelastic half-space. We solve the velocity form of the elasto(visco)dynamic equations using a continuous Galerkin Finite Element Method on an unstructured pentahedral mesh, which thus permits local spatial refinement in the vicinity of the fault. Friction sliding is coupled to the viscoelastic solid via rate- and state-dependent friction laws using the split-node technique. Our coupled formulation employs a picard-type non-linear solver with a fully implicit, first order accurate time integrator that utilises an adaptive time step that efficiently evolves the system through multiple seismic cycles. The implementation leverages advanced parallel solvers, preconditioners and linear algebra from the Portable Extensible Toolkit for Scientific Computing (PETSc) library. The model can treat heterogeneous frictional properties and stress states on the fault and surrounding solid as well as non-planar fault geometries. Preliminary tests show that the model successfully reproduces dynamic rupture on a vertical strike-slip fault in a half-space governed by rate-state friction with the ageing law.

Security proof of continuous-variable quantum key distribution using three coherent states

NASA Astrophysics Data System (ADS)

Brádler, Kamil; Weedbrook, Christian

2018-02-01

We introduce a ternary quantum key distribution (QKD) protocol and asymptotic security proof based on three coherent states and homodyne detection. Previous work had considered the binary case of two coherent states and here we nontrivially extend this to three. Our motivation is to leverage the practical benefits of both discrete and continuous (Gaussian) encoding schemes creating a best-of-both-worlds approach; namely, the postprocessing of discrete encodings and the hardware benefits of continuous ones. We present a thorough and detailed security proof in the limit of infinite signal states which allows us to lower bound the secret key rate. We calculate this is in the context of collective eavesdropping attacks and reverse reconciliation postprocessing. Finally, we compare the ternary coherent state protocol to other well-known QKD schemes (and fundamental repeaterless limits) in terms of secret key rates and loss.

Duration of shoot elongation in Scots pine varies within the crown and between years.

PubMed

Schiestl-Aalto, Pauliina; Nikinmaa, Eero; Mäkelä, Annikki

2013-10-01

Shoot elongation in boreal and temperate trees typically follows a sigmoid pattern where the onset and cessation of growth are related to accumulated effective temperature (thermal time). Previous studies on leader shoots suggest that while the maximum daily growth rate depends on the availability of resources to the shoot, the duration of the growth period may be an adaptation to long-term temperature conditions. However, other results indicate that the growth period may be longer in faster growing lateral shoots with higher availability of resources. This study investigates the interactions between the rate of elongation and the duration of the growth period in units of thermal time in lateral shoots of Scots pine (Pinus sylvestris). Length development of 202 lateral shoots were measured approximately three times per week during seven growing seasons in 2-5 trees per year in a mature stand and in three trees during one growing season in a sapling stand. A dynamic shoot growth model was adapted for the analysis to determine (1) the maximum growth rate and (2) the thermal time reached at growth completion. The relationship between those two parameters and its variation between trees and years was analysed using linear mixed models. The shoots with higher maximum growth rate within a crown continued to grow for a longer period in any one year. Higher July-August temperature of the previous summer implied a higher requirement of thermal time for growth completion. The results provide evidence that the requirement of thermal time for completion of lateral shoot extension in Scots pine may interact with resource availability to the shoot both from year to year and among shoots in a crown each year. If growing season temperatures rise in the future, this will affect not only the rate of shoot growth but its duration also.

The relationship between aerobic fitness and recovery from high-intensity exercise in infantry soldiers.

PubMed

Hoffman, J R

1997-07-01

The relationship between aerobic fitness and recovery from high-intensity exercise was examined in 197 infantry soldiers. Aerobic fitness was determined by a maximal-effort, 2,000-m run (RUN). High-intensity exercise consisted of three bouts of a continuous 140-m sprint with several changes of direction. A 2-minute passive rest separated each sprint. A fatigue index was developed by dividing the mean time of the three sprints by the fastest time. Times for the RUN were converted into standardized T scores and separated into five groups (group 1 had the slowest run time and group 5 had the fastest run time). Significant differences in the fatigue index were seen between group 1 (4.9 +/- 2.4%) and groups 3 (2.6 +/- 1.7%), 4 (2.3 +/- 1.6%), and 5 (2.3 +/- 1.3%). It appears that recovery from high-intensity exercise is improved at higher levels of aerobic fitness (faster time for the RUN). However, as the level of aerobic fitness improves above the population mean, no further benefit in the recovery rate from high-intensity exercise is apparent.

Seeing red: Americans driven into debt by medical bills. Results from a National Survey.

PubMed

Doty, Michelle M; Edwards, Jennifer N; Holmgren, Alyssa L

2005-08-01

New analysis of the 2003 Commonwealth Fund Biennial Health Insurance Survey reveals that an estimated 77 million Americans age 19 and older--nearly two of five (37%) adults--have difficulty paying medical bills, have accrued medical debt, or both. Working-age adults incur significantly higher rates of medical bill and debt problems than adults 65 and older, with rates highest among the uninsured. Even working-age adults who are continually insured have problems paying their medical bills and have medical debt. Unpaid medical bills and medical debt can limit access to health care: two-thirds of people with a medical bill or debt problem went without needed care because of cost--nearly three times the rate of those without these financial problems.

High efficiency cell-recycle continuous sodium gluconate production by Aspergillus niger using on-line physiological parameters association analysis to regulate feed rate rationally.

PubMed

Lu, Fei; Li, Chao; Wang, Zejian; Zhao, Wei; Chu, Ju; Zhuang, Yingping; Zhang, Siliang

2016-11-01

In this paper, a system of cell-recycle continuous fermentation for sodium gluconate (SG) production by Aspergillus niger (A. niger) was established. Based on initial continuous fermentation result (100.0h) with constant feed rate, an automatic feedback strategy to regulate feed rate using on-line physiological parameters (OUR and DO) was proposed and applied successfully for the first time in the improved continuous fermentation (240.5h). Due to less auxiliary time, highest SG production rate (31.05±0.29gL(-1)h(-1)) and highest yield (0.984±0.067molmol(-1)), overall SG production capacity (975.8±5.8gh(-1)) in 50-L fermentor of improved continuous fermentation increased more than 300.0% compared to that of batch fermentation. Improvement of mass transfer and dispersed mycelia morphology were the two major reasons responsible for the high SG production rate. This system had been successfully applied to industrial fermentation and SG production was greatly improved. Copyright © 2016 Elsevier Ltd. All rights reserved.

Why are breastfeeding rates low in Lebanon? a qualitative study

PubMed Central

2011-01-01

Background Breastfeeding is a cost-effective public health intervention that reduces infant morbidity and mortality in developing countries. In Lebanon, breastfeeding exclusivity and continuation rates are disappointingly low. This qualitative study aims at identifying barriers and promoters of breastfeeding in the Lebanese context by exploring mothers' perceptions and experiences in breastfeeding over a one year period. Methods We conducted focus group discussions in three hospitals in Beirut, Lebanon, and followed up 36 breastfeeding mothers with serial in-depth interviews for one year post-partum or until breastfeeding discontinuation. Results Themes generated from baseline interviews revealed several positive and negative perceptions of breastfeeding. Longitudinal follow up identified insufficient milk, fear of weight gain or breast sagging, pain, sleep deprivation, exhaustion, or maternal employment, as reasons for early breastfeeding discontinuation. Women who continued breastfeeding for one year were more determined to succeed and overcome any barrier, relying mostly on family support and proper time management. Conclusions Increasing awareness of future mothers about breast feeding difficulties, its benefits to children, mothers, and society at large may further promote breastfeeding, and improve exclusivity and continuation rates in Lebanon. A national strategy for early intervention during school years to increase young women's awareness may improve their self-confidence and determination to succeed in breastfeeding later. Moreover, prolonging maternity leave, having day-care facilities at work, creation of lactation peer support groups and hotlines, and training of doctors and nurses in proper lactation support may positively impact breastfeeding exclusivity and continuation rates. Further research is needed to assess the effectiveness of proposed interventions in the Lebanese context. PMID:21878101

Why are breastfeeding rates low in Lebanon? A qualitative study.

PubMed

Nabulsi, Mona

2011-08-30

Breastfeeding is a cost-effective public health intervention that reduces infant morbidity and mortality in developing countries. In Lebanon, breastfeeding exclusivity and continuation rates are disappointingly low. This qualitative study aims at identifying barriers and promoters of breastfeeding in the Lebanese context by exploring mothers' perceptions and experiences in breastfeeding over a one year period. We conducted focus group discussions in three hospitals in Beirut, Lebanon, and followed up 36 breastfeeding mothers with serial in-depth interviews for one year post-partum or until breastfeeding discontinuation. Themes generated from baseline interviews revealed several positive and negative perceptions of breastfeeding. Longitudinal follow up identified insufficient milk, fear of weight gain or breast sagging, pain, sleep deprivation, exhaustion, or maternal employment, as reasons for early breastfeeding discontinuation. Women who continued breastfeeding for one year were more determined to succeed and overcome any barrier, relying mostly on family support and proper time management. Increasing awareness of future mothers about breast feeding difficulties, its benefits to children, mothers, and society at large may further promote breastfeeding, and improve exclusivity and continuation rates in Lebanon. A national strategy for early intervention during school years to increase young women's awareness may improve their self-confidence and determination to succeed in breastfeeding later. Moreover, prolonging maternity leave, having day-care facilities at work, creation of lactation peer support groups and hotlines, and training of doctors and nurses in proper lactation support may positively impact breastfeeding exclusivity and continuation rates. Further research is needed to assess the effectiveness of proposed interventions in the Lebanese context.

Cortical Components of Reaction-Time during Perceptual Decisions in Humans.

PubMed

Dmochowski, Jacek P; Norcia, Anthony M

2015-01-01

The mechanisms of perceptual decision-making are frequently studied through measurements of reaction time (RT). Classical sequential-sampling models (SSMs) of decision-making posit RT as the sum of non-overlapping sensory, evidence accumulation, and motor delays. In contrast, recent empirical evidence hints at a continuous-flow paradigm in which multiple motor plans evolve concurrently with the accumulation of sensory evidence. Here we employ a trial-to-trial reliability-based component analysis of encephalographic data acquired during a random-dot motion task to directly image continuous flow in the human brain. We identify three topographically distinct neural sources whose dynamics exhibit contemporaneous ramping to time-of-response, with the rate and duration of ramping discriminating fast and slow responses. Only one of these sources, a parietal component, exhibits dependence on strength-of-evidence. The remaining two components possess topographies consistent with origins in the motor system, and their covariation with RT overlaps in time with the evidence accumulation process. After fitting the behavioral data to a popular SSM, we find that the model decision variable is more closely matched to the combined activity of the three components than to their individual activity. Our results emphasize the role of motor variability in shaping RT distributions on perceptual decision tasks, suggesting that physiologically plausible computational accounts of perceptual decision-making must model the concurrent nature of evidence accumulation and motor planning.

Does raising type 1 error rate improve power to detect interactions in linear regression models? A simulation study.

PubMed

Durand, Casey P

2013-01-01

Statistical interactions are a common component of data analysis across a broad range of scientific disciplines. However, the statistical power to detect interactions is often undesirably low. One solution is to elevate the Type 1 error rate so that important interactions are not missed in a low power situation. To date, no study has quantified the effects of this practice on power in a linear regression model. A Monte Carlo simulation study was performed. A continuous dependent variable was specified, along with three types of interactions: continuous variable by continuous variable; continuous by dichotomous; and dichotomous by dichotomous. For each of the three scenarios, the interaction effect sizes, sample sizes, and Type 1 error rate were varied, resulting in a total of 240 unique simulations. In general, power to detect the interaction effect was either so low or so high at α = 0.05 that raising the Type 1 error rate only served to increase the probability of including a spurious interaction in the model. A small number of scenarios were identified in which an elevated Type 1 error rate may be justified. Routinely elevating Type 1 error rate when testing interaction effects is not an advisable practice. Researchers are best served by positing interaction effects a priori and accounting for them when conducting sample size calculations.

40 CFR 60.1315 - Must I meet other requirements for continuous monitoring?

Code of Federal Regulations, 2012 CFR

2012-07-01

... continuous monitoring? 60.1315 Section 60.1315 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Requirements § 60.1315 Must I meet other requirements for continuous monitoring? You must also monitor three... at the inlet of your particulate matter air pollution control device. (c) Carbon feed rate if...

40 CFR 60.1315 - Must I meet other requirements for continuous monitoring?

Code of Federal Regulations, 2010 CFR

2010-07-01

... continuous monitoring? 60.1315 Section 60.1315 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Requirements § 60.1315 Must I meet other requirements for continuous monitoring? You must also monitor three... at the inlet of your particulate matter air pollution control device. (c) Carbon feed rate if...

40 CFR 60.1315 - Must I meet other requirements for continuous monitoring?

Code of Federal Regulations, 2014 CFR

2014-07-01

... continuous monitoring? 60.1315 Section 60.1315 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Requirements § 60.1315 Must I meet other requirements for continuous monitoring? You must also monitor three... at the inlet of your particulate matter air pollution control device. (c) Carbon feed rate if...

40 CFR 60.1315 - Must I meet other requirements for continuous monitoring?

Code of Federal Regulations, 2013 CFR

2013-07-01

... continuous monitoring? 60.1315 Section 60.1315 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Requirements § 60.1315 Must I meet other requirements for continuous monitoring? You must also monitor three... at the inlet of your particulate matter air pollution control device. (c) Carbon feed rate if...

40 CFR 60.1315 - Must I meet other requirements for continuous monitoring?

Code of Federal Regulations, 2011 CFR

2011-07-01

... continuous monitoring? 60.1315 Section 60.1315 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Requirements § 60.1315 Must I meet other requirements for continuous monitoring? You must also monitor three... at the inlet of your particulate matter air pollution control device. (c) Carbon feed rate if...

Characterization of a detector chain using a FPGA-based time-to-digital converter to reconstruct the three-dimensional coordinates of single particles at high flux

NASA Astrophysics Data System (ADS)

Nogrette, F.; Heurteau, D.; Chang, R.; Bouton, Q.; Westbrook, C. I.; Sellem, R.; Clément, D.

2015-11-01

We report on the development of a novel FPGA-based time-to-digital converter and its implementation in a detection chain that records the coordinates of single particles along three dimensions. The detector is composed of micro-channel plates mounted on top of a cross delay line and connected to fast electronics. We demonstrate continuous recording of the timing signals from the cross delay line at rates up to 4.1 × 106 s-1 and three-dimensional reconstruction of the coordinates up to 3.2 × 106 particles per second. From the imaging of a calibrated structure we measure the in-plane resolution of the detector to be 140(20) μm at a flux of 3 × 105 particles per second. In addition, we analyze a method to estimate the resolution without placing any structure under vacuum, a significant practical improvement. While we use UV photons here, the results of this work apply to the detection of other kinds of particles.

Dynamic leaching studies of 48 MWd/kgU UO2 commercial spent nuclear fuel under oxic conditions

NASA Astrophysics Data System (ADS)

Serrano-Purroy, D.; Casas, I.; González-Robles, E.; Glatz, J. P.; Wegen, D. H.; Clarens, F.; Giménez, J.; de Pablo, J.; Martínez-Esparza, A.

2013-03-01

The leaching of a high-burn-up spent nuclear fuel (48 MWd/KgU) has been studied in a carbonate-containing solution and under oxic conditions using a Continuously Stirred Tank Flow-Through Reactor (CSTR). Two samples of the fuel, one prepared from the centre of the pellet (labelled CORE) and another one from the fuel pellet periphery, enriched with the so-called High Burn-Up Structure (HBS, labelled OUT) have been used.For uranium and actinides, the results showed that U, Np, Am and Cm gave very similar normalized dissolution rates, while Pu showed slower dissolution rates for both samples. In addition, dissolution rates were consistently two to four times lower for OUT sample compared to CORE sample.Considering the fission products release the main results are that Y, Tc, La and Nd dissolved very similar to uranium; while Cs, Sr, Mo and Rb have up to 10 times higher dissolution rates. Rh, Ru and Zr seemed to have lower dissolution rates than uranium. The lowest dissolution rates were found for OUT sample.Three different contributions were detected on uranium release, modelled and attributed to oxidation layer, fines and matrix release.

Remission and Recovery in the Treatment for Adolescents with Depression Study (TADS): Acute and Long-term Outcomes

PubMed Central

Kennard, Betsy D.; Silva, Susan G.; Tonev, Simon; Rohde, Paul; Hughes, Jennifer L.; Vitiello, Benedetto; Kratochvil, Christopher J.; Curry, John F.; Emslie, Graham J.; Reinecke, Mark; March, John

2010-01-01

Objective We examine remission rate probabilities, recovery rates, and residual symptoms across 36 weeks in the Treatment for Adolescents with Depression Study (TADS). Method TADS, a multisite clinical trial, randomized 439 adolescents with major depressive disorder (MDD) to 12 weeks of treatment to fluoxetine (FLX), cognitive behavioral therapy (CBT), their combination (COMB), or pill placebo (PBO). The PBO group, treated openly after week 12, was not included in the subsequent analyses. Treatment differences in remission rates and probabilities of remission over time are compared. Recovery rates in remitters at week 12 (acute phase remitters) and week 18 (continuation phase remitters) are summarized. We also examined whether residual symptoms at the end of 12 weeks of acute treatment predicted later remission. Results At Week 36, the estimated remission rates for intention-to-treat cases were: COMB: 60%, FLX: 55%; CBT: 64%; overall: 60%. Paired comparisons reveal that at week 24 all active treatments converge on remission outcomes. The recovery rate at Week 36 was 65% for acute phase remitters and 71% for continuation phase remitters, with no significant between-treatment differences in recovery rates. Residual symptoms at the end of acute treatment predicted failure to achieve remission at weeks 18 and 36. Conclusions The majority of depressed adolescents in all three treatment modalities achieved remission at the end of nine months of treatment. PMID:19127172

Biodegradation of PCE and TCE in landfill leachate predicted from concentrations of molecular hydrogen: a case study.

PubMed

Gonsoulin, Mary E; Wilson, Barbara H; Wilson, John T

2004-12-01

The Refuse Hideaway Landfill (23-acre) received municipal, commercial, and industrial waste between 1974 and 1988. It was designed as a "natural attenuation" landfill and no provision was made to collect and treat contaminated water. Natural biological degradation through sequential reductive dechlorination had been an important mechanism for natural attenuation at the site. We used the concentration of hydrogen to forecast whether reductive dechlorination would continue over time at particular locations in the plume. Based on published literature, reductive dechlorination and natural attenuation of PCE, TCE, and cis-DCE can be expected in the aquifer if the concentration of molecular hydrogen in monitoring wells are adequate (> 1 nanomolar). Reductive dechlorination can be expected to continue as the ground water moves down gradient. Natural attenuation through reductive dechlorination is not expected in flow paths that originate at down gradient monitoring wells with low concentrations of molecular hydrogen (< 1 nanomolar). In three monitoring wells at the margin of the landfill and in five monitoring wells down gradient of the landfill, ground water maintained a molecular hydrogen concentration, ranging from 1.30 to 9.17 nanomolar, that is adequate for reductive dechlorination. In three of the monitoring wells far down gradient of the landfill, the concentration of molecular hydrogen (0.33 to 0.83 nanomolar) was not adequate to support reductive dechlorination. In wells with adequate concentrations of hydrogen, the concentrations of chlorinated volatile organic compounds were attenuated over time, or concentrations of chlorinated volatile organics were below the detection limit. In wells with inadequate concentrations of hydrogen, the concentrations of chlorinated organic compounds attenuated at a slower rate over time. In wells with adequate hydrogen the first order rate of attenuation of PCE, TCE, cis-DCE and total chlorinated volatile organic compounds varies from 0.38 to 0.18 per year. In wells without adequate hydrogen the rate varies from 0.015 to 0.006 per year.

Continuous vs. intermittent work with Canadian Forces NBC clothing.

PubMed

McLellan, T M; Jacobs, I; Bain, J B

1993-07-01

This study examined the benefits of work and rest schedules on soldiers' work tolerance (WTT) while wearing various levels of nuclear, biological and chemical (NBC) defence protective clothing in a warm environment (30 degrees C and 50% R.H.). Eight unacclimatized males were assigned to exercise at either a light (walking 1.11 m.s-1 0% grade, alternating with lifting 10 kg) or heavy metabolic rate (walking 1.33 m.s-1 7.5% grade, alternating with lifting 20 kg). Subjects were tested wearing three levels of clothing protection: combat clothing (L); combats and a semi-permeable NBC overgarment with the hood down (M); combats and NBC overgarment, gloves, boots and respirator (H). For each clothing configuration, subjects were evaluated using both a "continuous" exercise protocol and an intermittent work and rest schedule. WTT was defined as the time until rectal temperature (Tre) reached 39.3 degrees C, heart rate reached 95% maximum, dizziness or nausea precluded further exercise, or 5 h had elapsed. Assuming a resting VO2 of 4 ml.kg-1 x min-1 an average metabolic rate was calculated for all trials. A decreasing hyperbolic function described the relationship between WTT and metabolic rate for M and H. These relationships facilitate quantification of appropriate work and rest schedules if the metabolic rate of a task is known.

Quantifying the Uncertainty in Discharge Data Using Hydraulic Knowledge and Uncertain Gaugings

NASA Astrophysics Data System (ADS)

Renard, B.; Le Coz, J.; Bonnifait, L.; Branger, F.; Le Boursicaud, R.; Horner, I.; Mansanarez, V.; Lang, M.

2014-12-01

River discharge is a crucial variable for Hydrology: as the output variable of most hydrologic models, it is used for sensitivity analyses, model structure identification, parameter estimation, data assimilation, prediction, etc. A major difficulty stems from the fact that river discharge is not measured continuously. Instead, discharge time series used by hydrologists are usually based on simple stage-discharge relations (rating curves) calibrated using a set of direct stage-discharge measurements (gaugings). In this presentation, we present a Bayesian approach to build such hydrometric rating curves, to estimate the associated uncertainty and to propagate this uncertainty to discharge time series. The three main steps of this approach are described: (1) Hydraulic analysis: identification of the hydraulic controls that govern the stage-discharge relation, identification of the rating curve equation and specification of prior distributions for the rating curve parameters; (2) Rating curve estimation: Bayesian inference of the rating curve parameters, accounting for the individual uncertainties of available gaugings, which often differ according to the discharge measurement procedure and the flow conditions; (3) Uncertainty propagation: quantification of the uncertainty in discharge time series, accounting for both the rating curve uncertainties and the uncertainty of recorded stage values. In addition, we also discuss current research activities, including the treatment of non-univocal stage-discharge relationships (e.g. due to hydraulic hysteresis, vegetation growth, sudden change of the geometry of the section, etc.).

Continual Screening of Patients Using mHealth: The Rolling Score Concept Applied to Sleep Medicine.

PubMed

Zluga, Claudio; Modre-Osprian, Robert; Kastner, Peter; Schreier, Günter

2016-01-01

Continual monitoring of patients utilizing mHealth-based telemonitoring applications are more and more used for individual management of patients. A new approach in risk assessment called Rolling Score Concept uses standardized questionnaires for continual scoring of individuals' health state through electronic patient reported outcome (ePRO). Using self-rated questionnaires and adding a specific Time Schedule to each question result in a movement of the questionnaires' scores over time, the Rolling Score. A text-processing pipeline was implemented with KNIME analytics platform to extract a Score Mapping Rule Set for three standardized screening questionnaires in the field of sleep medicine. A feasibility study was performed in 10 healthy volunteers equipped with a mHealth application on a smartphone and a sleep tracker. Results show that the proposed Rolling Score Concept is feasible and deviations of scores are in a reasonable range (< 7%), sustaining the new approach. However, further studies are required for verification. In addition, parameter quantification could avoid incorrect subjective evaluation by substitution of questions with sensor data.

Hypoglossal-facial nerve anastomosis and rehabilitation in patients with complete facial palsy: cohort study of 30 patients followed up for three years

PubMed Central

Toffola, Elena Dalla; Pavese, Chiara; Cecini, Miriam; Petrucci, Lucia; Ricotti, Susanna; Bejor, Maurizio; Salimbeni, Grazia; Biglioli, Federico; Klersy, Catherine

2014-01-01

Summary Our study evaluates the grade and timing of recovery in 30 patients with complete facial paralysis (House-Brackmann grade VI) treated with hypoglossal-facial nerve (XII-VII) anastomosis and a long-term rehabilitation program, consisting of exercises in facial muscle activation mediated by tongue movement and synkinesis control with mirror feedback. Reinnervation after XII-VII anastomosis occurred in 29 patients, on average 5.4 months after surgery. Three years after the anastomosis, 23.3% of patients had grade II, 53.3% grade III, 20% grade IV and 3.3% grade VI ratings on the House-Brackmann scale. Time to reinnervation was associated with the final House-Brackmann grade. Our study demonstrates that patients undergoing XII-VII anastomosis and a long-term rehabilitation program display a significant recovery of facial symmetry and movement. The recovery continues for at least three years after the anastomosis, meaning that prolonged follow-up of these patients is advisable. PMID:25473738

99mTc-DTPA diuretic renal scintigraphy in dogs with nephroureterolithiasis

PubMed Central

Hecht, Silke; Lawson, S. Meg; Lane, India F.; Sharp, Dorothy E.; Daniel, Gregory B.

2010-01-01

This study evaluated the results of diuretic renal scintigraphy in dogs with urolithiasis. Eighty-three kidneys with nephroureterolithiasis +/− renal pelvis/ureteral dilation were included in the study. Sixty-three kidneys showed a non-obstructive pattern, with a steep drop or gradual downward slope of renal time-activity curve (TAC). Excretion half-time of radiopharmaceutical (T1/2) was 3.99 (2.99 to 7.95) min. Three kidneys showed an obstructive pattern, with continuous rise of the TAC and median T1/2 of −10.71 (−5.20 to −17.56) min. Fifteen kidneys had non-diagnostic studies characterized by flat TAC. Individual kidney glomerular filtration rate was < 0.5 mL/min/kg body weight in most non-diagnostic studies. Diuretic renal scintigraphy appears to be a useful adjunct modality to rule out or confirm ureteral obstruction in dogs. Additional diagnostic procedures may be necessary to achieve a definitive diagnosis in cases of severely impaired renal function. PMID:21358928

The Continued Demise of Columbia Glacier: Insights On Dynamic Change

NASA Astrophysics Data System (ADS)

Enderlin, E. M.; Hamilton, G. S.; O'Neel, S.; Bartholomaus, T. C.

2016-12-01

Columbia Glacier, Alaska, has served as the archetype for the retreat phase of the tidewater glacier cycle for the past three decades. Since the mid-1980s, the terminus has retreated 16 kilometers and the two major tributaries have thinned by > 400 m. This retreat and thinning led to separation of the tributaries in the late 2000s. Since their separation, the tributaries have exhibited strikingly different dynamic behaviors over seasonal to inter-annual time scales as they continue to adjust to the long-term changes in glacier geometry. Here we use a combination of ground, airborne, and satellite remote sensing datasets to characterize the dynamic behavior of the Columbia Glacier system. We focus on the time period following tributary separation, when the observational record is most abundant, but also investigate longer-term changes in dynamics such as the reorganization of ice flow in the eastern tributary (Figure 1). From the mid 2000s through 2012, the tributaries thinned at comparable rates ( 25 m/yr) based on repeat DEM differencing. Their behavior diverged in 2012, when the eastern tributary appeared to stabilize but the western tributary continued its sustained thinning trend. Thinning resumed along the eastern tributary in late 2013, and was accompanied by modest terminus retreat and acceleration. In contrast, the rate of thinning dramatically increased along the western tributary as it began to rapidly retreat in late 2013. These changes coincided with the three-fold increase in flow speed and pronounced increase in iceberg discharge from the western tributary. Although variations in the timing and magnitude of the recent dynamic changes can be at least partially explained by differences in the geometries of the tributaries, the dynamic behavior of Columbia Glacier's major tributaries is unlikely to be totally independent of environmental perturbations (i.e., entirely driven by the long-term dynamic adjustment). To assess the influence of environmental perturbations on the dynamic behavior of the glacier, we compare weekly to multi-year changes in glacier dynamics constructed from our airborne and satellite remotely-sensed datasets to time series of frontal ablation (i.e., submarine melting and iceberg calving) and surface mass balance compiled from ground-based observations.

Changes in kinematics and arm-leg coordination during a 100-m breaststroke swim.

PubMed

Oxford, Samuel W; James, Rob S; Price, Michael J; Payton, Carl J; Duncan, Michael J

2017-08-01

The purpose of this study was to compare arm-leg coordination and kinematics during 100 m breaststroke in 26 (8 female; 18 male) specialist breaststroke swimmers. Laps were recorded using three 50-Hz underwater cameras. Heart rate and blood lactate were measured pre- and post-swim. Arm-leg coordination was defined using coordination phases describing continuity between recovery and propulsive phases of upper and lower limbs: coordination phase 1 (time between end of leg kick and start of the arm pull phases); and coordination phase 2 (time between end of arm pull and start of leg kick phases). Duration of stroke phases, coordination phases, swim velocity, stroke length (SL), stroke rate (SR) and stroke index (SI) were analysed during the last three strokes of each lap that were unaffected by turning or finishing. Significant changes in velocity, SI and SL (P < 0.05) were found between laps. Both sexes showed significant increase (P < 0.05) in heart rate and blood lactate pre- to post-swim. Males had significantly (P < 0.01) faster swim velocities resulting from longer SLs (P = 0.016) with no difference in SR (P = 0.064). Sex differences in kinematic parameters can be explained by anthropometric differences providing males with increased propelling efficiency.

Real-time assessment of critical quality attributes of a continuous granulation process.

PubMed

Fonteyne, Margot; Vercruysse, Jurgen; Díaz, Damián Córdoba; Gildemyn, Delphine; Vervaet, Chris; Remon, Jean Paul; De Beer, Thomas

2013-02-01

There exists the intention to shift pharmaceutical manufacturing of solid dosage forms from traditional batch production towards continuous production. The currently applied conventional quality control systems, based on sampling and time-consuming off-line analyses in analytical laboratories, would annul the advantages of continuous processing. It is clear that real-time quality assessment and control is indispensable for continuous production. This manuscript evaluates strengths and weaknesses of several complementary Process Analytical Technology (PAT) tools implemented in a continuous wet granulation process, which is part of a fully continuous from powder-to-tablet production line. The use of Raman and NIR-spectroscopy and a particle size distribution analyzer is evaluated for the real-time monitoring of critical parameters during the continuous wet agglomeration of an anhydrous theophylline- lactose blend. The solid state characteristics and particle size of the granules were analyzed in real-time and the critical process parameters influencing these granule characteristics were identified. The temperature of the granulator barrel, the amount of granulation liquid added and, to a lesser extent, the powder feed rate were the parameters influencing the solid state of the active pharmaceutical ingredient (API). A higher barrel temperature and a higher powder feed rate, resulted in larger granules.

Constant Flux of Spatial Niche Partitioning through High-Resolution Sampling of Magnetotactic Bacteria.

PubMed

He, Kuang; Gilder, Stuart A; Orsi, William D; Zhao, Xiangyu; Petersen, Nikolai

2017-10-15

Magnetotactic bacteria (MTB) swim along magnetic field lines in water. They are found in aquatic habitats throughout the world, yet knowledge of their spatial and temporal distribution remains limited. To help remedy this, we took MTB-bearing sediment from a natural pond, mixed the thoroughly homogenized sediment into two replicate aquaria, and then counted three dominant MTB morphotypes (coccus, spirillum, and rod-shaped MTB cells) at a high spatiotemporal sampling resolution: 36 discrete points in replicate aquaria were sampled every ∼30 days over 198 days. Population centers of the MTB coccus and MTB spirillum morphotypes moved in continual flux, yet they consistently inhabited separate locations, displaying significant anticorrelation. Rod-shaped MTB were initially concentrated toward the northern end of the aquaria, but at the end of the experiment, they were most densely populated toward the south. The finding that the total number of MTB cells increased over time during the experiment argues that population reorganization arose from relative changes in cell division and death and not from migration. The maximum net growth rates were 10, 3, and 1 doublings day -1 and average net growth rates were 0.24, 0.11, and 0.02 doublings day -1 for MTB cocci, MTB spirilla, and rod-shaped MTB, respectively; minimum growth rates for all three morphotypes were -0.03 doublings day -1 Our results suggest that MTB cocci and MTB spirilla occupy distinctly different niches: their horizontal positioning in sediment is anticorrelated and under constant flux. IMPORTANCE Little is known about the horizontal distribution of magnetotactic bacteria in sediment or how the distribution changes over time. We therefore measured three dominant magnetotactic bacterium morphotypes at 36 places in two replicate aquaria each month for 7 months. We found that the spatial positioning of population centers changed over time and that the two most abundant morphotypes (MTB cocci and MTB spirilla) occupied distinctly different niches in the aquaria. Maximum and average growth and death rates were quantified for each of the three morphotypes based on 72 sites that were measured six times. The findings provided novel insight into the differential behavior of noncultured magnetotactic bacteria. Copyright © 2017 American Society for Microbiology.

Noncontingent reinforcement without extinction plus differential reinforcement of alternative behavior during treatment of problem behavior.

PubMed

Fritz, Jennifer N; Jackson, Lynsey M; Stiefler, Nicole A; Wimberly, Barbara S; Richardson, Amy R

2017-07-01

The effects of noncontingent reinforcement (NCR) without extinction during treatment of problem behavior maintained by social positive reinforcement were evaluated for five individuals diagnosed with autism spectrum disorder. A continuous NCR schedule was gradually thinned to a fixed-time 5-min schedule. If problem behavior increased during NCR schedule thinning, a continuous NCR schedule was reinstated and NCR schedule thinning was repeated with differential reinforcement of alternative behavior (DRA) included. Results showed an immediate decrease in all participants' problem behavior during continuous NCR, and problem behavior maintained at low levels during NCR schedule thinning for three participants. Problem behavior increased and maintained at higher rates during NCR schedule thinning for two other participants; however, the addition of DRA to the intervention resulted in decreased problem behavior and increased mands. © 2017 Society for the Experimental Analysis of Behavior.

Reactive transport of uranium in fractured crystalline rock: Upscaling in time and distance

DOE PAGES

Dittrich, Timothy M.; Reimus, Paul W.

2015-09-29

In this study, batch adsorption and breakthrough column experiments were conducted to evaluate uranium transport through altered material that fills fractures in a granite rock system at the Grimsel Test Site in Switzerland at pH 6.9 and 7.9. The role of adsorption and desorption kinetics was evaluated with reactive transport modeling by comparing one-, two-, and three-site models. Emphasis was placed on describing long desorption tails that are important for upscaling in time and distance. The effect of increasing pH in injection solutions was also evaluated. For pH 6.9, a three-site model with forward rate constants between 0.07 and 0.8more » ml g –1 h –1, reverse rate constants between 0.001 and 0.06 h –1, and site densities of 1.3, 0.104, and 0.026 μmol g –1 for ‘weak/fast’, ‘strong/slow’, and ‘very strong/very slow’ sites provided the best fits. For pH 7.9, a three-site model with forward rate constants between 0.05 and 0.8 mL g –1 h –1, reverse rate constants between 0.001 and 0.6 h –1, and site densities of 1.3, 0.039, and 0.013 μmol g –1 for a ‘weak/fast’, ‘strong/slow’, and ‘very strong/very slow’ sites provided the best fits. Column retardation coefficients (R d) were 80 for pH 6.9 and 10.3 for pH 7.9. Model parameters determined from the batch and column experiments were used in 50 year large-scale simulations for continuous and pulse injections and indicated that a three-site model is necessary at pH 6.9, although a K d-type equilibrium partition model with one-site was adequate for large scale predictions at pH 7.9. Batch experiments were useful for predicting early breakthrough times in the columns while column experiments helped differentiate the relative importance of sorption sites and desorption rate constants on transport.« less

Diversity of rhizosphere soil arbuscular mycorrhizal fungi in various soybean cultivars under different continuous cropping regimes.

PubMed

Jie, Weiguang; Liu, Xiaorui; Cai, Baiyan

2013-01-01

Recent studies have shown that continuous cropping in soybean causes substantial changes to the microbial community in rhizosphere soil. In this study, we investigated the effects of continuous cropping for various time periods on the diversity of rhizosphere soil arbuscular mycorrhizal (AM) fungi in various soybean cultivars at the branching stage. The soybean cultivars Heinong 37 (an intermediate cultivar), Heinong 44 (a high-fat cultivar) and Heinong 48 (a high-protein cultivar) were seeded in a field and continuously cropped for two or three years. We analyzed the diversity of rhizosphere soil AM fungi of these soybean plants at the branching stage using morphological and denaturing gradient gel electrophoresis (DGGE) techniques. The clustering analysis of unweighted pair-group method with arithmetic averages (UPGMA) was then used to investigate the AM fungal community shifts. The results showed that increasing the number of years of continuous cropping can improve the colonization rate of AM fungi in different soybean cultivars at the branching stage. The dominant AM fungi in the experimental fields were Funneliformismosseae and Glomus spp. The number of years of continuous cropping and the soybean cultivar both had obvious effects on the diversity of AM fungi, which was consistent with the results of colonization rate analysis. This study establishes a basis for screening dominant AM fungi of soybean. In addition, the results of this study may be useful for the development of AM fungal inoculants.

Diversity of Rhizosphere Soil Arbuscular Mycorrhizal Fungi in Various Soybean Cultivars under Different Continuous Cropping Regimes

PubMed Central

Jie, Weiguang; Liu, Xiaorui; Cai, Baiyan

2013-01-01

Recent studies have shown that continuous cropping in soybean causes substantial changes to the microbial community in rhizosphere soil. In this study, we investigated the effects of continuous cropping for various time periods on the diversity of rhizosphere soil arbuscular mycorrhizal (AM) fungi in various soybean cultivars at the branching stage. The soybean cultivars Heinong 37 (an intermediate cultivar), Heinong 44 (a high-fat cultivar) and Heinong 48 (a high-protein cultivar) were seeded in a field and continuously cropped for two or three years. We analyzed the diversity of rhizosphere soil AM fungi of these soybean plants at the branching stage using morphological and denaturing gradient gel electrophoresis (DGGE) techniques. The clustering analysis of unweighted pair-group method with arithmetic averages (UPGMA) was then used to investigate the AM fungal community shifts. The results showed that increasing the number of years of continuous cropping can improve the colonization rate of AM fungi in different soybean cultivars at the branching stage. The dominant AM fungi in the experimental fields were Funneliformismosseae and Glomus spp. The number of years of continuous cropping and the soybean cultivar both had obvious effects on the diversity of AM fungi, which was consistent with the results of colonization rate analysis. This study establishes a basis for screening dominant AM fungi of soybean. In addition, the results of this study may be useful for the development of AM fungal inoculants. PMID:23977368

SAM-CE; A Three Dimensional Monte Carlo Code for the Dolution of the Forward Neutron and Forward and Adjoint Gamma Ray Transport Equations. Revision C

DTIC Science & Technology

1974-07-31

Multiple scoring regions are permitted and these may be either finite volume regions or point detectors or both. Other sccres of interest, e.g., collision... Multiplicities ...... . . . . 43 2,3.5.2 Photon Production Cross Sections. . 44 2.3.5.3 Anisotropy of Photon Production . . 44 2.3.5.4 Continuous...hepting, count rates, etc., are calculated as functions of energy, time and position. Multiple scoring regions are permitted and these may be either

[Evaluation of heart impact in the 100 m extreme intensity sport using near-infrared non-invasive muscle oxygen detecting device and sports heart rate detection technology].

PubMed

Wang, Pei-Yong; Long, Fei-Xiao; Fu, Lan-Ying; Li, Yue; Ding, Hai-Shu; Qu, An-Lian; Zhou, Xiao-Ping

2010-02-01

Using continuous two wavelength near-infrared technology to detect the variation in the consistency of oxygen hemoglobin in the muscle and the sports heart rate wireless real time collection technology, we devised the real time muscle tissue oxygenation and instantaneous heart rate experiment scheme and implemented it for the process of the 100 m run with two parameters given simultaneously. The experiment shows that the concentration of the oxygen hemoglobin in the muscle tissue continues decreasing after the end of the 100 m run, and the time interval between the moment when the concentration of the oxygen hemoglobin attains the minimum value and the moment when the athletes finish the 100 m run is (6.65 +/- 1.10) sec; while the heart rate continues increasing after the end of the 100 m run, and the time interval between the moment when the heart rate attains the maximum value and the moment when the athletes finish the 100 m run is (8.00 +/- 1.57) sec. The results show that the two wavelength near-infrared tissue oxygenation detection technology and the sports heart rate real time collection equipment can accurately measure the sports tissue oxygenation and the heart rate in the extreme intensity sport, and reveal the process of muscle oxygen transportation and consumption and its dynamic character with the heart rate in the extreme intensity sport.

17β-estradiol in runoff as affected by various poultry litter application strategies.

PubMed

Delaune, P B; Moore, P A

2013-02-01

Steroidal hormones, which are excreted by all mammalian species, have received increasing attention in recent years due to potential environmental implications. The objective of this study was to evaluate 17β-estradiol concentrations in runoff water from plots receiving poultry litter applications using various management strategies. Treatments included the effects of 1) aluminum sulfate (alum) application rates to poultry litter; 2) time until the first runoff event occurs after poultry litter application; 3) poultry litter application rate; 4) fertilizer type; and 5) litter from birds fed modified diets. Rainfall simulators were used to cause continuous runoff from fertilized plots. Runoff samples were collected and analyzed for 17β-estradiol concentrations. Results showed that increasing alum additions to poultry litter decreased 17β-estradiol concentrations in runoff water. A significant exponential decline in 17β-estradiol runoff was also observed with increasing time until the first runoff event after litter application. Concentrations of 17β-estradiol in runoff water increased with increasing litter application rate and remained above background concentrations after three runoff events at higher application rates. Management practices such as diet modification and selection of fertilizer type were also shown to affect 17β-estradiol concentrations in runoff water. Although results from these experiments typically represented a worst case scenario since runoff events generally occurred immediately after litter application, the contaminant loss from pastures fertilized with poultry litter can be expected to be much lower than continual estradiol loadings observed from waste water treatment plants. Management practices such as alum amendment and application timing can significantly reduce the risk of 17β-estradiol losses in the environment. Copyright © 2012 Elsevier B.V. All rights reserved.

Continuously Variable Rating: a new, simple and logical procedure to evaluate original scientific publications

PubMed Central

Silva, Mauricio Rocha e

2011-01-01

OBJECTIVE: Impact Factors (IF) are widely used surrogates to evaluate single articles, in spite of known shortcomings imposed by cite distribution skewness. We quantify this asymmetry and propose a simple computer-based procedure for evaluating individual articles. METHOD: (a) Analysis of symmetry. Journals clustered around nine Impact Factor points were selected from the medical “Subject Categories” in Journal Citation Reports 2010. Citable items published in 2008 were retrieved and ranked by granted citations over the Jan/2008 - Jun/2011 period. Frequency distribution of cites, normalized cumulative cites and absolute cites/decile were determined for each journal cluster. (b) Positive Predictive Value. Three arbitrarily established evaluation classes were generated: LOW (1.3≤IF<2.6); MID: (2.6≤IF<3.9); HIGH: (IF≥3.9). Positive Predictive Value for journal clusters within each class range was estimated. (c) Continuously Variable Rating. An alternative evaluation procedure is proposed to allow the rating of individually published articles in comparison to all articles published in the same journal within the same year of publication. The general guiding lines for the construction of a totally dedicated software program are delineated. RESULTS AND CONCLUSIONS: Skewness followed the Pareto Distribution for (1

A real-time approach for heart rate monitoring using a Hilbert transform in seismocardiograms.

PubMed

Jafari Tadi, Mojtaba; Lehtonen, Eero; Hurnanen, Tero; Koskinen, Juho; Eriksson, Jonas; Pänkäälä, Mikko; Teräs, Mika; Koivisto, Tero

2016-11-01

Heart rate monitoring helps in assessing the functionality and condition of the cardiovascular system. We present a new real-time applicable approach for estimating beat-to-beat time intervals and heart rate in seismocardiograms acquired from a tri-axial microelectromechanical accelerometer. Seismocardiography (SCG) is a non-invasive method for heart monitoring which measures the mechanical activity of the heart. Measuring true beat-to-beat time intervals from SCG could be used for monitoring of the heart rhythm, for heart rate variability analysis and for many other clinical applications. In this paper we present the Hilbert adaptive beat identification technique for the detection of heartbeat timings and inter-beat time intervals in SCG from healthy volunteers in three different positions, i.e. supine, left and right recumbent. Our method is electrocardiogram (ECG) independent, as it does not require any ECG fiducial points to estimate the beat-to-beat intervals. The performance of the algorithm was tested against standard ECG measurements. The average true positive rate, positive prediction value and detection error rate for the different positions were, respectively, supine (95.8%, 96.0% and ≃0.6%), left (99.3%, 98.8% and ≃0.001%) and right (99.53%, 99.3% and ≃0.01%). High correlation and agreement was observed between SCG and ECG inter-beat intervals (r  >  0.99) for all positions, which highlights the capability of the algorithm for SCG heart monitoring from different positions. Additionally, we demonstrate the applicability of the proposed method in smartphone based SCG. In conclusion, the proposed algorithm can be used for real-time continuous unobtrusive cardiac monitoring, smartphone cardiography, and in wearable devices aimed at health and well-being applications.

Convective heat transfer measurements in a vapour-liquid-liquid three-phase direct contact heat exchanger

NASA Astrophysics Data System (ADS)

Mahood, Hameed B.; Campbell, A. N.; Baqir, Ali Sh.; Sharif, A. O.; Thorpe, R. B.

2018-06-01

Energy usage is increasing around the world due to the continued development of technology, and population growth. Solar energy is a promising low-grade energy resource that can be harvested and utilised in different applications, such solar heater systems, which are used in both domestic and industrial settings. However, the implementation of an efficient energy conversion system or heat exchanger would enhance such low-grade energy processes. The direct contact heat exchanger could be the right choice due to its ability to efficiently transfer significant amounts of heat, simple design, and low cost. In this work, the heat transfer associated with the direct contact condensation of pentane vapour bubbles in a three-phase direct contact condenser is investigated experimentally. Such a condenser could be used in a cycle with a solar water heater and heat recovery systems. The experiments on the steady state operation of the three-phase direct contact condenser were carried out using a short Perspex tube of 70 cm in total height and an internal diameter of 4 cm. Only a height of 48 cm was active as the direct contact condenser. Pentane vapour, (the dispersed phase) with three different initial temperatures (40° C, 43.5° C and 47.5° C) was directly contacted with water (the continuous phase) at 19° C. The experimental results showed that the total heat transfer rate per unit volume along the direct contact condenser gradually decreased upon moving higher up the condenser. Additionally, the heat transfer rate increases with increasing mass flow rate ratio, but no significant effect on the heat transfer rate of varying the initial temperature of the dispersed phase was seen. Furthermore, both the outlet temperature of the continuous phase and the void fraction were positively correlated with the total heat transfer rate per unit volume, with no considerable effect of the initial temperature difference between the dispersed and continuous phases.

Convective heat transfer measurements in a vapour-liquid-liquid three-phase direct contact heat exchanger

NASA Astrophysics Data System (ADS)

Mahood, Hameed B.; Campbell, A. N.; Baqir, Ali Sh.; Sharif, A. O.; Thorpe, R. B.

2017-12-01

Energy usage is increasing around the world due to the continued development of technology, and population growth. Solar energy is a promising low-grade energy resource that can be harvested and utilised in different applications, such solar heater systems, which are used in both domestic and industrial settings. However, the implementation of an efficient energy conversion system or heat exchanger would enhance such low-grade energy processes. The direct contact heat exchanger could be the right choice due to its ability to efficiently transfer significant amounts of heat, simple design, and low cost. In this work, the heat transfer associated with the direct contact condensation of pentane vapour bubbles in a three-phase direct contact condenser is investigated experimentally. Such a condenser could be used in a cycle with a solar water heater and heat recovery systems. The experiments on the steady state operation of the three-phase direct contact condenser were carried out using a short Perspex tube of 70 cm in total height and an internal diameter of 4 cm. Only a height of 48 cm was active as the direct contact condenser. Pentane vapour, (the dispersed phase) with three different initial temperatures (40° C, 43.5° C and 47.5° C) was directly contacted with water (the continuous phase) at 19° C. The experimental results showed that the total heat transfer rate per unit volume along the direct contact condenser gradually decreased upon moving higher up the condenser. Additionally, the heat transfer rate increases with increasing mass flow rate ratio, but no significant effect on the heat transfer rate of varying the initial temperature of the dispersed phase was seen. Furthermore, both the outlet temperature of the continuous phase and the void fraction were positively correlated with the total heat transfer rate per unit volume, with no considerable effect of the initial temperature difference between the dispersed and continuous phases.

A continuous system for biocatalytic hydrogenation of CO2 to formate.

PubMed

Mourato, Cláudia; Martins, Mónica; da Silva, Sofia M; Pereira, Inês A C

2017-07-01

In this work a novel bioprocess for hydrogenation of CO 2 to formate was developed, using whole cell catalysis by a sulfate-reducing bacterium. Three Desulfovibrio species were tested (D. vulgaris Hildenborough, D. alaskensis G20, and D. desulfuricans ATCC 27774), of which D. desulfuricans showed the highest activity, producing 12mM of formate in batch, with a production rate of 0.09mMh -1 . Gene expression analysis indicated that among the three formate dehydrogenases and five hydrogenases, the cytoplasmic FdhAB and the periplasmic [FeFe] HydAB are the main enzymes expressed in D. desulfuricans in these conditions. The new bioprocess for continuous formate production by D. desulfuricans had a maximum specific formate production rate of 14mMg dcw -1 h -1 , and more than 45mM of formate were obtained with a production rate of 0.40mMh -1 . This is the first report of a continuous process for biocatalytic formate production. Copyright © 2017 Elsevier Ltd. All rights reserved.

Inflammatory breast cancer: enhanced local control with hyperfractionated radiotherapy and infusional vincristine, ifosfamide and epirubicin.

PubMed

Gurney, H; Harnett, P; Kefford, R; Boyages, J

1998-06-01

Local control rate for inflammatory breast cancer (IBC) is < 50% with standard chemotherapy-radiotherapy regimen. Nineteen women (age range 40-65, median 50 years) with IBC (18 patients) or with a primary tumour of > 10 cm (one patient) received a novel treatment comprising hyperfractionated radiotherapy (HFRT) sandwiched between two cycles of infusional chemotherapy using vincristine, ifosfamide and epirubicin (VIE). The primary endpoint was local control. VIE was continuously infused for six weeks via a Hickman's line using a Deltec CADD-1 ambulatory pump. Ifosfamide (3 gm/m2) mixed with equi-dose mesna was infused for seven days and alternated every week with an infusion of epirubicin (50 mg/m2) mixed with vincristine (1.5 mg/m2). HFRT consisted of 1.5 Gy twice daily for 34 frct (51 Gy) followed by a boost of 15 Gy in 10 frct. The total treatment time was less than 22 weeks. Median follow-up was 37 months. Local control rate was 58%. Three patients failed to respond initially and five relapsed in the breast at a median time of 36.8 months. Median overall and disease-free survival was 18 and 25.3 months respectively. Toxicity from VIE was minimal (WHO gd 3 emesis--two patients, gd 3 mucositis--one patient, neutropenic sepsis--three patients). Radiotherapy caused moist desquamation in 17/19 patients. Twenty-four central lines were complicated by seven line infections, three thromboses, and one extravasation. The local control rate of 58% with VIE + HFRT appears similar to reported chemoradiotherapy regimen, although the treatment time of 22 weeks is much shorter than other regimens which take up to 12 months. Toxicity is acceptable. Hickman-related complications need to be reduced. The study is ongoing.

Zero velocity interval detection based on a continuous hidden Markov model in micro inertial pedestrian navigation

NASA Astrophysics Data System (ADS)

Sun, Wei; Ding, Wei; Yan, Huifang; Duan, Shunli

2018-06-01

Shoe-mounted pedestrian navigation systems based on micro inertial sensors rely on zero velocity updates to correct their positioning errors in time, which effectively makes determining the zero velocity interval play a key role during normal walking. However, as walking gaits are complicated, and vary from person to person, it is difficult to detect walking gaits with a fixed threshold method. This paper proposes a pedestrian gait classification method based on a hidden Markov model. Pedestrian gait data are collected with a micro inertial measurement unit installed at the instep. On the basis of analyzing the characteristics of the pedestrian walk, a single direction angular rate gyro output is used to classify gait features. The angular rate data are modeled into a univariate Gaussian mixture model with three components, and a four-state left–right continuous hidden Markov model (CHMM) is designed to classify the normal walking gait. The model parameters are trained and optimized using the Baum–Welch algorithm and then the sliding window Viterbi algorithm is used to decode the gait. Walking data are collected through eight subjects walking along the same route at three different speeds; the leave-one-subject-out cross validation method is conducted to test the model. Experimental results show that the proposed algorithm can accurately detect different walking gaits of zero velocity interval. The location experiment shows that the precision of CHMM-based pedestrian navigation improved by 40% when compared to the angular rate threshold method.

Development of an Intermediate-Scale Aerobic Bioreactor to Regenerate Nutrients from Inedible Crop Residues

NASA Technical Reports Server (NTRS)

Finger, Barry W.; Strayer, Richard F.

1994-01-01

Three Intermediate-Scale Aerobic Bioreactors were designed, fabricated, and operated. They utilized mixed microbial communities to bio-degrade plant residues. The continuously stirred tank reactors operated at a working volume of 8 L, and the average oxygen mass transfer coefficient, k(sub L)a, was 0.01 s(exp -1). Mixing time was 35 s. An experiment using inedible wheat residues, a replenishment rate of 0.125/day, and a solids loading rate of 20 gdw/day yielded a 48% reduction in biomass. Bioreactor effluent was successfully used to regenerate a wheat hydroponic nutrient solution. Over 80% of available potassium, calcium, and other minerals were recovered and recycled in the 76-day wheat growth experiment.

SVM based colon polyps classifier in a wireless active stereo endoscope.

PubMed

Ayoub, J; Granado, B; Mhanna, Y; Romain, O

2010-01-01

This work focuses on the recognition of three-dimensional colon polyps captured by an active stereo vision sensor. The detection algorithm consists of SVM classifier trained on robust feature descriptors. The study is related to Cyclope, this prototype sensor allows real time 3D object reconstruction and continues to be optimized technically to improve its classification task by differentiation between hyperplastic and adenomatous polyps. Experimental results were encouraging and show correct classification rate of approximately 97%. The work contains detailed statistics about the detection rate and the computing complexity. Inspired by intensity histogram, the work shows a new approach that extracts a set of features based on depth histogram and combines stereo measurement with SVM classifiers to correctly classify benign and malignant polyps.

Electrocardiogram provides a continuous heart rate faster than oximetry during neonatal resuscitation.

PubMed

Katheria, Anup; Rich, Wade; Finer, Neil

2012-11-01

To compare the time required to obtain a continuous audible heart rate signal from an electrocardiogram (ECG) monitor and pulse oximeter (PO) in infants requiring resuscitation. Infants who had both ECG and PO placed during resuscitation were analyzed using video and analog recordings. The median times from arrival until the ECG electrodes and PO sensor were placed, and the time to achieve audible tones from the devices, were compared. Forty-six infants had ECG and PO data. Thirty infants were very low birth weight (23-30 weeks). There was a difference in the median total time to place either device (26 vs 38 seconds; P = .04), and a difference (P < .001) in the time to achieve an audible heart rate signal after ECG lead (2 seconds) versus PO probe (24 seconds) placement. In infants weighing >1500 g (n = 16), the median time (interquartile range) to place the ECG was 20 seconds (14-43) whereas the time to place the PO was 36 seconds (28-56) (P = .74). The median times (interquartile range) to acquire a signal from the ECG and PO were 4 seconds (1-6) and 32 seconds (15-40, P = .001), respectively. During the first minutes of resuscitation, 93% of infants had an ECG heart rate compared with only 56% for PO. Early application of ECG electrodes during infant resuscitation can provide the resuscitation team with a continuous audible heart rate, and its use may improve the timeliness of appropriate critical interventions.

A kinetic model for estimating net photosynthetic rates of cos lettuce leaves under pulsed light.

PubMed

Jishi, Tomohiro; Matsuda, Ryo; Fujiwara, Kazuhiro

2015-04-01

Time-averaged net photosynthetic rate (P n) under pulsed light (PL) is known to be affected by the PL frequency and duty ratio, even though the time-averaged photosynthetic photon flux density (PPFD) is unchanged. This phenomenon can be explained by considering that photosynthetic intermediates (PIs) are pooled during light periods and then consumed by partial photosynthetic reactions during dark periods. In this study, we developed a kinetic model to estimate P n of cos lettuce (Lactuca sativa L. var. longifolia) leaves under PL based on the dynamics of the amount of pooled PIs. The model inputs are average PPFD, duty ratio, and frequency; the output is P n. The rates of both PI accumulation and consumption at a given moment are assumed to be dependent on the amount of pooled PIs at that point. Required model parameters and three explanatory variables (average PPFD, frequency, and duty ratio) were determined for the simulation using P n values under PL based on several combinations of the three variables. The model simulation for various PL levels with a wide range of time-averaged PPFDs, frequencies, and duty ratios further demonstrated that P n under PL with high frequencies and duty ratios was comparable to, but did not exceed, P n under continuous light, and also showed that P n under PL decreased as either frequency or duty ratio was decreased. The developed model can be used to estimate P n under various light environments where PPFD changes cyclically.

Multistate transitional models for measuring adherence to breast cancer screening: A population-based longitudinal cohort study with over two million women.

PubMed

Sutradhar, R; Gu, S; Paszat, L F

2017-06-01

Objective Prior work on the disparities among women in breast cancer screening adherence has been methodologically limited. This longitudinal study determines and examines the factors associated with becoming adherent. Methods In a cohort of Canadian women aged 50-74, a three-state transitional model was used to examine adherence to screening for breast cancer. The proportion of time spent being non-adherent with screening was calculated for each woman during her observation window. Using age as the time scale, a relative rate multivariable regression was implemented under the three-state transitional model, to examine the association between covariates (all time-varying) and the rate of becoming adherent. Results The cohort consisted of 2,537,960 women with a median follow-up of 8.46 years. Nearly 31% of women were continually up-to-date with breast screening. Once a woman was non-adherent, the rate of becoming adherent was higher among longer term residents (relative rate = 1.289, 95% confidence interval 1.275-1.302), those from wealthier neighbourhoods, and those who had an identifiable primary care provider who was female or had graduated in Canada. Conclusion Individual and physician-level characteristics play an important role in a woman's adherence to screening. This work improves the quality of evidence regarding disparities among women in adherence to breast cancer screening and provides a novel methodological foundation to investigate adherence for other types of screening, including cervix and colorectal cancer screening.

The Influence of Prior Choices on Current Choice

PubMed Central

de la Piedad, Xochitl; Field, Douglas; Rachlin, Howard

2006-01-01

Three pigeons chose between random-interval (RI) and tandem, continuous-reinforcement, fixed-interval (crf-FI) reinforcement schedules by pecking either of two keys. As long as a pigeon pecked on the RI key, both keys remained available. If a pigeon pecked on the crf-FI key, then the RI key became unavailable and the crf-FI timer began to time out. With this procedure, once the RI key was initially pecked, the prospective value of both alternatives remained constant regardless of time spent pecking on the RI key without reinforcement (RI waiting time). Despite this constancy, the rate at which pigeons switched from the RI to the crf-FI decreased sharply as RI waiting time increased. That is, prior choices influenced current choice—an exercise effect. It is argued that such influence (independent of reinforcement contingencies) may serve as a sunk-cost commitment device in self-control situations. In a second experiment, extinction was programmed if RI waiting time exceeded a certain value. Rate of switching to the crf-FI first decreased and then increased as the extinction point approached, showing sensitivity to both prior choices and reinforcement contingencies. In a third experiment, crf-FI availability was limited to a brief window during the RI waiting time. When constrained in this way, switching occurred at a high rate regardless of when, during the RI waiting time, the crf-FI became available. PMID:16602373

PREDICTION OF SOLAR FLARE SIZE AND TIME-TO-FLARE USING SUPPORT VECTOR MACHINE REGRESSION

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

Boucheron, Laura E.; Al-Ghraibah, Amani; McAteer, R. T. James

We study the prediction of solar flare size and time-to-flare using 38 features describing magnetic complexity of the photospheric magnetic field. This work uses support vector regression to formulate a mapping from the 38-dimensional feature space to a continuous-valued label vector representing flare size or time-to-flare. When we consider flaring regions only, we find an average error in estimating flare size of approximately half a geostationary operational environmental satellite (GOES) class. When we additionally consider non-flaring regions, we find an increased average error of approximately three-fourths a GOES class. We also consider thresholding the regressed flare size for the experimentmore » containing both flaring and non-flaring regions and find a true positive rate of 0.69 and a true negative rate of 0.86 for flare prediction. The results for both of these size regression experiments are consistent across a wide range of predictive time windows, indicating that the magnetic complexity features may be persistent in appearance long before flare activity. This is supported by our larger error rates of some 40 hr in the time-to-flare regression problem. The 38 magnetic complexity features considered here appear to have discriminative potential for flare size, but their persistence in time makes them less discriminative for the time-to-flare problem.« less

[Effect of excess ethanol on the growth of yeasts of the genus Candida during continuous cultivation].

PubMed

Shkidchenko, A N; Shul'ga, A V; Gurina, L V

1988-01-01

The effect of flow rates and a specific ethanol load on the growth of Candida utilis and Candida krusei was studied in the process of one-step and three-step cultivation. The productive capacity of fermenters and the economic coefficient of yeast biomass production were shown to depend on the ability of microbial populations to assimilate a certain quantity of a carbon substrate per unit time. When a specific ethanol load exceeds the optimal one, the respiratory activity of a population and the economic coefficient of growth fall down whereas the accumulation of metabolites in the cultural broth increases. The steady state of biomass can be maintained in the process of continuous cultivation by inhibiting the yeast growth with an excess of ethanol.

The accuracy and efficacy of real-time continuous glucose monitoring sensor in Chinese diabetes patients: a multicenter study.

PubMed

Zhou, Jian; Lv, Xiaofeng; Mu, Yiming; Wang, Xianling; Li, Jing; Zhang, Xingguang; Wu, Jinxiao; Bao, Yuqian; Jia, Weiping

2012-08-01

The purpose of this multicenter study was to investigate the accuracy of a real-time continuous glucose monitoring sensor in Chinese diabetes patients. In total, 48 patients with type 1 or 2 diabetes from three centers in China were included in the study. The MiniMed Paradigm(®) 722 insulin pump (Medtronic, Northridge, CA) was used to monitor the real-time continuous changes of blood glucose levels for three successive days. Venous blood of the subjects was randomly collected every 15 min for seven consecutive hours on the day when the subjects were wearing the sensor. Reference values were provided by the YSI(®) 2300 STAT PLUS™ glucose and lactate analyzer (YSI Life Sciences, Yellow Springs, OH). In total, 1,317 paired YSI-sensor values were collected from the 48 patients. Of the sensor readings, 88.3% (95% confidence interval, 0.84-0.92) were within±20% of the YSI values, and 95.7% were within±30% of the YSI values. Clarke and consensus error grid analyses showed that the ratios of the YSI-sensor values in Zone A to the values in Zone B were 99.1% and 99.9%, respectively. Continuous error grid analysis showed that the ratios of the YSI-sensor values in the region of accurate reading, benign errors, and erroneous reading were 96.4%, 1.8%, and 1.8%, respectively. The mean absolute relative difference (ARD) for all subjects was 10.4%, and the median ARD was 7.8%. Bland-Altman analysis detected a mean blood glucose level of 3.84 mg/dL. Trend analysis revealed that 86.1% of the difference of the rates of change between the YSI values and the sensor readings occurred within the range of 1 mg/dL/min. The Paradigm insulin pump has high accuracy in both monitoring the real-time continuous changes and predicting the trend of changes in blood glucose level. However, actual clinical manifestations should be taken into account for diagnosis of hypoglycemia.

Effect of time on dyeing wastewater treatment

NASA Astrophysics Data System (ADS)

Ye, Tingjin; Chen, Xin; Xu, Zizhen; Chen, Xiaogang; Shi, Liang; He, Lingfeng; Zhang, Yongli

2018-03-01

The preparation of carboxymethylchitosan wrapping fly-ash adsorbent using high temperature activated fly ash and sodium carboxymethyl chitosan (CWF), as with the iron-carbon micro-electrolysis process simulation and actual printing and dyeing wastewater. The effects of mixing time and static time on decolorization ratio, COD removing rate and turbidness removing rate were investigated. The experimental results show that the wastewater stirring times on the decolorization rate and COD removal rate and turbidity removal rate influence, with increasing of the stirring time, three showed a downward trend, and reached the peak at 10 min time; wastewater time on the decolorization ratio and COD removing efficiency and turbidness removing rate influence, along with standing time increase, three who declined and reached the maximum in 30min time.

Communication partner training for health care professionals in an inpatient rehabilitation setting: A parallel randomised trial.

PubMed

Heard, Renee; O'Halloran, Robyn; McKinley, Kathryn

2017-06-01

The purpose of this study is to determine if the E-Learning Plus communication partner training (CPT) programme is as effective as the Supported Conversation for Adults with Aphasia (SCA TM ) CPT programme in improving healthcare professionals' confidence and knowledge communicating with patients with aphasia. Forty-eight healthcare professionals working in inpatient rehabilitation participated. Participants were randomised to one of the CPT programmes. The three outcome measures were self-rating of confidence, self-rating of knowledge and a test of knowledge of aphasia. Measures were taken pre-, immediately post- and 3-4 months post-training. Data were analysed using mixed between within ANOVAs. Homogeneity of variance was adequate for self-rating of confidence and test of knowledge of aphasia data to continue analysis. There was a statistically significant difference in self-rating of confidence and knowledge of aphasia for both interventions across time. No statistically significant difference was found between the two interventions. Both CPT interventions were associated with an increase in health care professionals' confidence and knowledge of aphasia, but neither programme was superior. As the E-Learning Plus CPT programme is more accessible and sustainable in the Australian healthcare context, further work will continue on this CPT programme.

Paramagnetic capture mode magnetophoretic microseparator for high efficiency blood cell separations.

PubMed

Han, Ki-Ho; Frazier, A Bruno

2006-02-01

This paper presents the characterization of continuous single-stage and three-stage cascade paramagnetic capture (PMC) mode magnetophoretic microseparators for high efficiency separation of red and white blood cells from diluted whole blood based on their native magnetic properties. The separation mechanism for both PMC microseparators is based on a high gradient magnetic separation (HGMS) method. This approach enables separation of blood cells without the use of additives such as magnetic beads. Experimental results for the single-stage PMC microseparator show that 91.1% of red blood cells were continuously separated from the sample at a volumetric flow rate of 5 microl h-1. In addition, the three-stage cascade PMC microseparator continuously separated 93.5% of red blood cells and 97.4% of white blood cells from whole blood at a volumetric flow rate of 5 microl h-1.

Chaos and unpredictability in evolution of cooperation in continuous time

NASA Astrophysics Data System (ADS)

You, Taekho; Kwon, Minji; Jo, Hang-Hyun; Jung, Woo-Sung; Baek, Seung Ki

2017-12-01

Cooperators benefit others with paying costs. Evolution of cooperation crucially depends on the cost-benefit ratio of cooperation, denoted as c . In this work, we investigate the infinitely repeated prisoner's dilemma for various values of c with four of the representative memory-one strategies, i.e., unconditional cooperation, unconditional defection, tit-for-tat, and win-stay-lose-shift. We consider replicator dynamics which deterministically describes how the fraction of each strategy evolves over time in an infinite-sized well-mixed population in the presence of implementation error and mutation among the four strategies. Our finding is that this three-dimensional continuous-time dynamics exhibits chaos through a bifurcation sequence similar to that of a logistic map as c varies. If mutation occurs with rate μ ≪1 , the position of the bifurcation sequence on the c axis is numerically found to scale as μ0.1, and such sensitivity to μ suggests that mutation may have nonperturbative effects on evolutionary paths. It demonstrates how the microscopic randomness of the mutation process can be amplified to macroscopic unpredictability by evolutionary dynamics.

U.S. dental school applicants and enrollees, 2006 and 2007 entering classes.

PubMed

Okwuje, Ifie; Anderson, Eugene; Siaya, Laura; Brown, L Jackson; Valachovic, Richard W

2008-11-01

The number of applicants to dental schools in the United States continues to rise at a double-digit rate, 12 percent from 2005 to 2006 and 14 percent from 2006 to 2007. The number of applicants to the 2006 and 2007 years' entering classes of U.S. dental schools was 12,500 and 13,700, respectively. The number of first-time enrollees (4,600) in 2007 was the highest recorded since 1989. Men continue to comprise the majority of all applicants, 55 percent in 2006 and 53 percent in 2007. However, the percentage of women applicants to each school ranged from a third to more than half. Underrepresented minority (URM) applicants comprised 12 percent of the applicant pools in both 2006 and 2007. For the 2007 entering class, URM enrollees comprised 13 percent of enrollees. As in previous years, in 2007, the largest number of applicants and enrollees came from states that are among the largest in population in the United States: California, Texas, New York, and Florida. Grade point average and Dental Admission Test scores were the highest in more than a decade. More than three out of four of the 2007 first-time, first-year enrollees earned a baccalaureate degree either in biological/life or physical sciences or in health. Regardless of major field of study, the percent rates of enrollment generally exceeded 30 percent, though there were exceptions (e.g., engineering and education). The majority of enrollees to the 2007 entering classes were twenty-two or twenty-three years of age.

Healthcare Utilization Rates after Oregon's 2008 Medicaid Expansion: Within-and between-group differences over time among New, Returning, and Continuously Insured Enrollees

PubMed Central

O'Malley, Jean P.; Rosetti, Maureen O'Keeffe; Lowe, Robert A.; Angier, Heather; Gold, Rachel; Marino, Miguel; Hatch, Brigit; Hoopes, Megan; Bailey, Steffani R.; Heintzman, John; Gallia, Charles; DeVoe, Jennifer E.

2016-01-01

Background Although past research demonstrated that Medicaid expansions were associated with increased emergency department (ED) and primary care (PC) utilization, little is known about how long this increased utilization persists or whether post-coverage utilization is affected by prior insurance status. Objectives (1) To assess changes in ED, PC, mental and behavioral health care (MBHC), and specialty care visit rates among individuals gaining Medicaid over 24 months post-insurance gain; (2) To evaluate the association of previous insurance with utilization. Methods Using claims data, we conducted a retrospective cohort analysis of adults insured for 24 months following Oregon's 2008 Medicaid expansion. Utilization rates among 1,124 new and 1,587 returning enrollees were compared to those among 5,126 enrollees with continuous Medicaid coverage (≥1 year pre-expansion). Visit rates were adjusted for propensity score classes and geographic region. Results PC visit rates in both newly and returning insured individuals significantly exceeded those in the continuously insured in months four through 12, but were not significantly elevated in the second year. In contrast, ED utilization rates were significantly higher in returning insured compared to newly or continuously insured individuals and remained elevated over time. New visits to PC and specialist care were higher among those who gained Medicaid compared to the continuously insured throughout the study period. Conclusions Predicting the effect of insurance expansion on healthcare utilization should account for the prior coverage history of new enrollees. Additionally, utilization of outpatient services changes with time after insurance, so expansion evaluations should allow for rate stabilization. PMID:27547943

46 CFR 169.683 - Overcurrent protection, general.

Code of Federal Regulations, 2013 CFR

2013-10-01

... time delay; (2) Instantaneous short circuit protection; and (3) Repeated opening of the circuit in... above the full-load rating for continuous rated machines or the overload rating for special rated machines. ...

46 CFR 169.683 - Overcurrent protection, general.

Code of Federal Regulations, 2014 CFR

2014-10-01

... time delay; (2) Instantaneous short circuit protection; and (3) Repeated opening of the circuit in... above the full-load rating for continuous rated machines or the overload rating for special rated machines. ...

46 CFR 169.683 - Overcurrent protection, general.

Code of Federal Regulations, 2012 CFR

2012-10-01

... time delay; (2) Instantaneous short circuit protection; and (3) Repeated opening of the circuit in... above the full-load rating for continuous rated machines or the overload rating for special rated machines. ...

The economics of using prophylactic antibiotic-loaded bone cement in total knee replacement.

PubMed

Gutowski, C J; Zmistowski, B M; Clyde, C T; Parvizi, J

2014-01-01

The rate of peri-prosthetic infection following total joint replacement continues to rise, and attempts to curb this trend have included the use of antibiotic-loaded bone cement at the time of primary surgery. We have investigated the clinical- and cost-effectiveness of the use of antibiotic-loaded cement for primary total knee replacement (TKR) by comparing the rate of infection in 3048 TKRs performed without loaded cement over a three-year period versus the incidence of infection after 4830 TKRs performed with tobramycin-loaded cement over a later period of time of a similar duration. In order to adjust for confounding factors, the rate of infection in 3347 and 4702 uncemented total hip replacements (THR) performed during the same time periods, respectively, was also examined. There were no significant differences in the characteristics of the patients in the different cohorts. The absolute rate of infection increased when antibiotic-loaded cement was used in TKR. However, this rate of increase was less than the rate of increase in infection following uncemented THR during the same period. If the rise in the rate of infection observed in THR were extrapolated to the TKR cohort, 18 additional cases of infection would have been expected to occur in the cohort receiving antibiotic-loaded cement, compared with the number observed. Depending on the type of antibiotic-loaded cement that is used, its cost in all primary TKRs ranges between USD $2112.72 and USD $112 606.67 per case of infection that is prevented.

47 CFR 76.1611 - Political cable rates and classes of time.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 47 Telecommunication 4 2010-10-01 2010-10-01 false Political cable rates and classes of time. 76.1611 Section 76.1611 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) BROADCAST RADIO SERVICES MULTICHANNEL VIDEO AND CABLE TELEVISION SERVICE Notices § 76.1611 Political cable rates and...

47 CFR 76.1611 - Political cable rates and classes of time.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 47 Telecommunication 4 2011-10-01 2011-10-01 false Political cable rates and classes of time. 76.1611 Section 76.1611 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) BROADCAST RADIO SERVICES MULTICHANNEL VIDEO AND CABLE TELEVISION SERVICE Notices § 76.1611 Political cable rates and...

47 CFR 76.1611 - Political cable rates and classes of time.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 47 Telecommunication 4 2012-10-01 2012-10-01 false Political cable rates and classes of time. 76.1611 Section 76.1611 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) BROADCAST RADIO SERVICES MULTICHANNEL VIDEO AND CABLE TELEVISION SERVICE Notices § 76.1611 Political cable rates and...

47 CFR 76.1611 - Political cable rates and classes of time.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 47 Telecommunication 4 2014-10-01 2014-10-01 false Political cable rates and classes of time. 76.1611 Section 76.1611 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) BROADCAST RADIO SERVICES MULTICHANNEL VIDEO AND CABLE TELEVISION SERVICE Notices § 76.1611 Political cable rates and...

47 CFR 76.1611 - Political cable rates and classes of time.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 47 Telecommunication 4 2013-10-01 2013-10-01 false Political cable rates and classes of time. 76.1611 Section 76.1611 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) BROADCAST RADIO SERVICES MULTICHANNEL VIDEO AND CABLE TELEVISION SERVICE Notices § 76.1611 Political cable rates and...

Connectionist Architectures for Time Series Prediction of Dynamical Systems

NASA Astrophysics Data System (ADS)

Weigend, Andreas Sebastian

We investigate the effectiveness of connectionist networks for predicting the future continuation of temporal sequences. The problem of overfitting, particularly serious for short records of noisy data, is addressed by the method of weight-elimination: a term penalizing network complexity is added to the usual cost function in back-propagation. We describe the dynamics of the procedure and clarify the meaning of the parameters involved. From a Bayesian perspective, the complexity term can be usefully interpreted as an assumption about prior distribution of the weights. We analyze three time series. On the benchmark sunspot series, the networks outperform traditional statistical approaches. We show that the network performance does not deteriorate when there are more input units than needed. In the second example, the notoriously noisy foreign exchange rates series, we pick one weekday and one currency (DM vs. US). Given exchange rate information up to and including a Monday, the task is to predict the rate for the following Tuesday. Weight-elimination manages to extract a significant part of the dynamics and makes the solution interpretable. In the third example, the networks predict the resource utilization of a chaotic computational ecosystem for hundreds of steps forward in time.

Daily rhythms of food intake and feces reingestion in the degu, an herbivorous Chilean rodent: optimizing digestion through coprophagy.

PubMed

Kenagy, G J; Veloso, C; Bozinovic, F

1999-01-01

Animals must match their foraging and digestion to seasonal changes in availability and quality of food. When these parameters decline, the animal's performance limits for extracting energy and nutrients may be challenged. In the laboratory, we investigated daily patterns of food processing on a low-quality (high-fiber) diet of alfalfa in an herbivorous, day-active rodent, the degu (Octodon degus), which inhabits semiarid central Chile. We manipulated timing of food availability, from continuous availability down to as little as 5 h/d. Degus maintained weight while digesting only 53% of dry-matter consumption. With food continuously available in a metabolic cage, the animals ate more food and deposited about twice as much feces in the day as at night. Continuous 24-h behavioral observation revealed that degus were actually defecating at the same rate both night and day but then ingesting most of the feces they produced at night. Further experimental treatments challenged animals with limited periods of food availability that matched natural foraging patterns. With either 11 h of daytime food availability or only 5 h (in morning and afternoon periods of 2.5 h each), degus consumed as much food as those with 24-h food availability. Continuous 24-h behavioral observations revealed in the 11-h group that nearly all feces produced at night were reingested and nearly none were reingested in the day, whereas the 5-h group resorted to further coprophagy during the 6-h midday interval with no food. Despite these differences in timing of food intake and coprophagy in response to the three experimental treatments, the degus were defecating at the same rate both night and day, which indicated a constant rate of output from the colon. This suggests a range of adjustments of digestive physiology to the timing of gut function by balancing coprophagy with ingestion of food. Overall, 38% of 24-h feces production was reingested, and 87% of this coprophagy occurred at night. The ingestion of feces during parts of the day when food is unavailable provides for continued intake into the digestive tract and appears to represent an increase in overall efficiency of gut use.

The influence of micro-topography and external bioerosion on coral-reef-building organisms: recruitment, community composition and carbonate production over time

NASA Astrophysics Data System (ADS)

Mallela, Jennie

2018-03-01

The continued health and function of tropical coral reefs is highly dependent on the ability of reef-building organisms to build large, complex, three-dimensional structures that continue to accrete and evolve over time. The recent deterioration of reef health globally, including loss of coral cover, has resulted in significant declines in architectural complexity at a large, reef-scape scale. Interestingly, the fine-scale role of micro-structure in initiating and facilitating future reef development and calcium carbonate production has largely been overlooked. In this study, experimental substrates with and without micro-ridges were deployed in the lagoon at One Tree Island for 34 months. This study assessed how the presence or absence of micro-ridges promoted recruitment by key reef-building sclerobionts (corals and encrusters) and their subsequent development at micro (mm) and macro (cm) scales. Experimental plates were examined after 11 and 34 months to assess whether long-term successional and calcification processes on different micro-topographies led to convergent or divergent communities over time. Sclerobionts were most prevalent in micro-grooves when they were available. Interestingly, in shallow lagoon reef sites characterised by shoals of small parrotfish and low urchin abundance, flat substrates were also successfully recruited to. Mean rates of carbonate production were 374 ± 154 (SD) g CaCO3 m-2 yr-1 within the lagoon. Substrates with micro-ridges were characterised by significantly greater rates of carbonate production than smooth substrates. The orientation of the substrate and period of immersion also significantly impacted rates of carbonate production, with CaCO3 on cryptic tiles increasing by 28% between 11 and 34 months. In contrast, rates on exposed tiles declined by 35% over the same time. In conclusion, even at sites characterised by small-sized parrotfish and low urchin density, micro-topography is an important settlement niche clearly favouring sclerobiont early life-history processes and subsequent carbonate production.

A mathematical approach for evaluating Markov models in continuous time without discrete-event simulation.

PubMed

van Rosmalen, Joost; Toy, Mehlika; O'Mahony, James F

2013-08-01

Markov models are a simple and powerful tool for analyzing the health and economic effects of health care interventions. These models are usually evaluated in discrete time using cohort analysis. The use of discrete time assumes that changes in health states occur only at the end of a cycle period. Discrete-time Markov models only approximate the process of disease progression, as clinical events typically occur in continuous time. The approximation can yield biased cost-effectiveness estimates for Markov models with long cycle periods and if no half-cycle correction is made. The purpose of this article is to present an overview of methods for evaluating Markov models in continuous time. These methods use mathematical results from stochastic process theory and control theory. The methods are illustrated using an applied example on the cost-effectiveness of antiviral therapy for chronic hepatitis B. The main result is a mathematical solution for the expected time spent in each state in a continuous-time Markov model. It is shown how this solution can account for age-dependent transition rates and discounting of costs and health effects, and how the concept of tunnel states can be used to account for transition rates that depend on the time spent in a state. The applied example shows that the continuous-time model yields more accurate results than the discrete-time model but does not require much computation time and is easily implemented. In conclusion, continuous-time Markov models are a feasible alternative to cohort analysis and can offer several theoretical and practical advantages.

Effect of culture residence time on substrate uptake and storage by a pure culture of Thiothrix (CT3 strain) under continuous or batch feeding.

PubMed

Valentino, Francesco; Beccari, Mario; Villano, Marianna; Tandoi, Valter; Majone, Mauro

2017-05-25

A pure culture of the filamentous bacterium Thiothrix, strain CT3, was aerobically cultured in a chemostat under continuous acetate feeding at three different culture residence times (RT 6, 12 or 22 d) and the same volumetric organic load rate (OLR 0.12gCOD/L/d). Cells cultured at decreasing RT in the chemostat had an increasing transient response to acetate spikes in batch tests. The maximum specific acetate removal rate increased from 25 to 185mgCOD/gCOD/h, corresponding to a 1.8 to 8.1 fold higher respective steady-state rate in the chemostat. The transient response was mainly due to acetate storage in the form of poly(3-hydroxybutyrate) (PHB), whereas no growth response was observed at any RT. Interestingly, even though the storage rate also decreased as the RT increased, the storage yield increased from 0.41 to 0.50 COD/COD. This finding does not support the traditional view that storage plays a more important role as the transient response increases. The transient response of the steady-state cells was much lower than in cells cultured under periodic feeding (at 6 d RT, from 82 to 247mgCOD/gCOD/h), with the latter cells showing both storage and growth responses. On the other hand, even though steady-state cells had no growth response and their storage rate was also less, steady-state cells showed a higher storage yield than cells cultured under dynamic feeding. This suggests that in Thiothrix strain CT3, the growth response is triggered by periodic feeding, whereas the storage response is a constitutive mechanism, independent from previous acclimation to transient conditions. Copyright © 2016 Elsevier B.V. All rights reserved.

Characterization of a detector chain using a FPGA-based time-to-digital converter to reconstruct the three-dimensional coordinates of single particles at high flux

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

Nogrette, F.; Chang, R.; Bouton, Q.

We report on the development of a novel FPGA-based time-to-digital converter and its implementation in a detection chain that records the coordinates of single particles along three dimensions. The detector is composed of micro-channel plates mounted on top of a cross delay line and connected to fast electronics. We demonstrate continuous recording of the timing signals from the cross delay line at rates up to 4.1 × 10{sup 6} s{sup −1} and three-dimensional reconstruction of the coordinates up to 3.2 × 10{sup 6} particles per second. From the imaging of a calibrated structure we measure the in-plane resolution of themore » detector to be 140(20) μm at a flux of 3 × 10{sup 5} particles per second. In addition, we analyze a method to estimate the resolution without placing any structure under vacuum, a significant practical improvement. While we use UV photons here, the results of this work apply to the detection of other kinds of particles.« less

Management and outcomes of patients on preoperative plavix (clopidogrel) undergoing general thoracic surgery.

PubMed

Paul, Subroto; Stock, Cameron; Chiu, Ya-lin; Kansler, Amanda; Port, Jeffrey L; Lee, Paul C; Stiles, Brendon M; Nasar, Abu; Sedrakyan, Art; Altorki, Nasser K

2013-09-01

Plavix (clopidogrel) is a potent antiplatelet agent used to prevent thrombosis in a variety of clinical settings. The perioperative management of thoracic surgery patients who are on clopidogrel at the time of surgery is not well defined. We conducted this review to examine the perioperative management and outcomes of patients undergoing general thoracic surgical procedures. From January 2005 to January 2010, 165 patients on clopidogrel underwent 182 operative procedures. Three management strategies were identified: Group I: clopidogrel continued through surgery (n = 17), Group II: clopidogrel discontinued with a bridging agent (n = 44) and Group III clopidogrel discontinued without a bridging agent (n = 121). Propensity score matched cohorts (17 clopidogrel continued; 34 clopidogrel discontinued) were constructed based on age, clopidogrel indication, American Society of Anesthesiology status, and procedure and used to compare the impact of clopidogrel management on postoperative bleeding and cardiovascular morbidity. Unmatched analysis revealed a significantly higher rate of transfusion in the group of patients who continued on clopidogrel throughout the perioperative period, compared with patients who had clopidogrel discontinued. Although there were more cardiovascular events in Groups II and III, there were no significant differences between groups in postoperative mortality, myocardial infarction, stroke, or reoperation for bleeding. In propensity matched patients only the rate of postoperative transfusions was significantly higher in patients continued on clopidogrel compared with patients whose clopidogrel was discontinued (35.3 vs. 2.9%), p < 0.004. In selected patients, some thoracic surgical procedures can be performed safely on clopidogrel but are associated with higher rates of postoperative transfusion. Georg Thieme Verlag KG Stuttgart · New York.

Corrosion and runoff rates of Cu and three Cu-alloys in marine environments with increasing chloride deposition rate.

PubMed

Odnevall Wallinder, Inger; Zhang, Xian; Goidanich, Sara; Le Bozec, Nathalie; Herting, Gunilla; Leygraf, Christofer

2014-02-15

Bare copper sheet and three commercial Cu-based alloys, Cu15Zn, Cu4Sn and Cu5Al5Zn, have been exposed to four test sites in Brest, France, with strongly varying chloride deposition rates. The corrosion rates of all four materials decrease continuously with distance from the coast, i.e. with decreasing chloride load, and in the following order: Cu4Sn>Cu sheet>Cu15Zn>Cu5Al5Zn. The patina on all materials was composed of two main layers, Cu2O as the inner layer and Cu2(OH)3Cl as the outer layer, and with a discontinuous presence of CuCl in between. Additional minor patina constituents are SnO2 (Cu4Sn), Zn5(OH)6(CO3)2 (Cu15Zn and Cu5Al5Zn) and Zn6Al2(OH)16CO3·4H2O/Zn2Al(OH)6Cl·2H2O/Zn5Cl2(OH)8·H2O and Al2O3 (Cu5Al5Zn). The observed Zn- and Zn/Al-containing corrosion products might be important factors for the lower sensitivity of Cu15Zn and Cu5Al5Zn against chloride-induced atmospheric corrosion compared with Cu sheet and Cu4Sn. Decreasing corrosion rates with exposure time were observed for all materials and chloride loads and attributed to an improved adherence with time of the outer patina to the underlying inner oxide. Flaking of the outer patina layer was mainly observed on Cu4Sn and Cu sheet and associated with the gradual transformation of CuCl to Cu2(OH)3Cl of larger volume. After three years only Cu5Al5Zn remains lustrous because of a patina compared with the other materials that appeared brownish-reddish. Significantly lower release rates of metals compared with corresponding corrosion rates were observed for all materials. Very similar release rates of copper from all four materials were observed during the fifth year of marine exposure due to an outer surface patina that with time revealed similar constituents and solubility properties. Copyright © 2013 The Authors. Published by Elsevier B.V. All rights reserved.

[Study of continuous quality improvement for clinical laboratory processes via the platform of Hospital Group].

PubMed

Song, Wenqi; Shen, Ying; Peng, Xiaoxia; Tian, Jian; Wang, Hui; Xu, Lili; Nie, Xiaolu; Ni, Xin

2015-05-26

The program of continuous quality improvement in clinical laboratory processes for complete blood count (CBC) was launched via the platform of Beijing Children's Hospital Group in order to improve the quality of pediatric clinical laboratories. Fifteen children's hospitals of Beijing Children's Hospital group were investigated using the method of Chinese adapted continuous quality improvement with PDCA (Plan-Do-Check-Action). The questionnaire survey and inter-laboratory comparison was conducted to find the existing problems, to analyze reasons, to set forth quality targets and to put them into practice. Then, targeted training was conducted to 15 children's hospitals and the second questionnaire survey, self examinations by the clinical laboratories was performed. At the same time, the Group's online internal quality control platform was established. Overall effects of the program were evaluated so that lay a foundation for the next stage of PDCA. Both quality of control system documents and CBC internal quality control scheme for all of clinical laboratories were improved through this program. In addition, standardization of performance verification was also improved, especially with the comparable verification rate of precision and internal laboratory results up to 100%. In terms of instrument calibration and mandatory diagnostic rates, only three out of the 15 hospitals (20%) failed to pass muster in 2014 from 46.67% (seven out of the 15 hospitals) in 2013. The abnormal data of intraday precision variance coefficients of the five CBC indicator parameters (WBC, RBC, Hb, Plt and Hct) of all the 15 laboratories accounted for 1.2% (2/165) in 2014, a marked decrease from 9.6% (14/145) in 2013. While the number of the hospitals using only one horizontal quality control object for daily quality control has dropped to three from five. The 15 hospitals organized a total of 263 times of training in 2014 from 101 times in 2013, up 160%. The quality improvement program for the clinical laboratories launched via the Hospital Group platform can promote the joint development of the pediatric clinical laboratory discipline of all the member hospitals with remarkable improvement results, and the experience is recommendable for further rollout.

Impulsive Control for Continuous-Time Markov Decision Processes: A Linear Programming Approach

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

Dufour, F., E-mail: dufour@math.u-bordeaux1.fr; Piunovskiy, A. B., E-mail: piunov@liv.ac.uk

2016-08-15

In this paper, we investigate an optimization problem for continuous-time Markov decision processes with both impulsive and continuous controls. We consider the so-called constrained problem where the objective of the controller is to minimize a total expected discounted optimality criterion associated with a cost rate function while keeping other performance criteria of the same form, but associated with different cost rate functions, below some given bounds. Our model allows multiple impulses at the same time moment. The main objective of this work is to study the associated linear program defined on a space of measures including the occupation measures ofmore » the controlled process and to provide sufficient conditions to ensure the existence of an optimal control.« less

Global Change And Water Availability And Quality: Challenges Ahead

NASA Astrophysics Data System (ADS)

Larsen, M. C.; Ryker, S. J.

2012-12-01

The United States is in the midst of a continental-scale, multi-year water-resources experiment, in which society has not defined testable hypotheses or set the duration and scope of the experiment. What are we doing? We are expanding population at two to three times the national growth rate in our most water-scarce states, in the southwest, where water stress is already great and modeling predicts decreased streamflow by the middle of this century. We are expanding irrigated agriculture from the west into the east, particularly to the southeastern states, where increased competition for ground and surface water has urban, agricultural, and environmental interests at odds, and increasingly, in court. We are expanding our consumption of pharmaceutical and personal care products to historic high levels and disposing of them in surface and groundwater, through sewage treatment plants and individual septic systems that were not designed to treat them. These and other examples of our national-scale experiment are likely to continue well into the 21st century. This experiment and related challenges will continue and likely intensify as non-climatic and climatic factors, such as predicted rising temperature and changes in the distribution of precipitation in time and space, continue to develop.

Increased dead space in face mask continuous positive airway pressure in neonates.

PubMed

Hishikawa, Kenji; Fujinaga, Hideshi; Ito, Yushi

2017-01-01

Continuous positive airway pressure (CPAP) by face mask is commonly performed in newborn resuscitation. We evaluated the effect of face mask CPAP on system dead space. Face mask CPAP increases dead space. A CPAP model study. We estimated the volume of the inner space of the mask. We devised a face mask CPAP model, in which the outlet of the mask was covered with plastic; and three modified face mask CPAP models, in which holes were drilled near to the cushion of the covered face mask to alter the air exit. We passed a continuous flow of 21% oxygen through each model and we controlled the inner pressure to 5 cmH 2 O by adjusting the flow-relief valve. To evaluate the ventilation in the inner space of each model, we measured the oxygen concentration rise time, that is, the time needed for the oxygen concentration of each model to reach 35% after the oxygen concentration of the continuous flow was raised from 21% to 40%. The volume of inner space of the face mask was 38.3 ml. Oxygen concentration rise time in the face mask CPAP model was significantly longer at various continuous flow rates and points of the inner space of the face mask compared with that of the modified face mask CPAP model. Our study indicates that face mask CPAP leads to an increase in dead space and a decrease in ventilation efficiency under certain circumstances. Pediatr Pulmonol. 2017;52:107-111. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Effect of Solids Retention Time on the Denitrification Potential of Anaerobically Digested Swine Waste

NASA Astrophysics Data System (ADS)

Kinyua, Maureen Njoki

Three continuously stirred tank reactors (CSTR) were operated in semi continuous mode treating swine waste using anaerobic digestion. The reactors were used to test the effect of solid retention time (SRT) on CH4 yield, total ammonia nitrogen (TAN) concentrations, % volatile solids (VS), chemical oxygen demand (COD) and volatile fatty acids (VFA) removal, readily biodegradable COD concentration and the denitrification potential for the effluent in a biological nutrient removal (BNR) system. During Phase I of the study, the three reactors were operated at the same 28 day SRT for 16 weeks. SRTs were then changed during the 12 week Phase II period. The SRTs studied were 14, 21 and 28 days, with the same organic loading rate (OLR) of 1.88 ± 0.2 kg VS/ m3-day. The reactor with the lowest SRT (14 days) had the highest VS and VFA removal at 73.6 and 67.6% and lowest TAN concentration at 0.78 g NH4+-N/L, followed by the 21 day and 28 day reactors. This was likely due to the fast microbial growth rates and substrate utilization rates in this reactor compared with the other two. The 14 day reactor had the highest CH4 yield at 0.33 m3CH 4/kg VS added and readily biodegradable COD concentration at 0.93 COD/L. The variations in CH4 yield and readily biodegradable COD concentrations between the three reactors were not statistically significant. Denitrification potential for the reactors was 1.20, 0.73 and 0.56 g COD/g N for 14, 21 and 28 day reactors, respectively, and the differences were statistically significant. None of the reactors achieved a denitrification potential of 5 g COD/g N, the amount required to use effluent of anaerobically digested swine waste as an internal carbon source in a BNR. This was attributed to operating conditions such as freezing and thawing of the raw swine waste that maximized CH4 yield and lowered the readily biodegradable COD concentration. In addition the 14 day reactor had low TAN concentrations thus increasing the denitrification potential of the centrate from that reactor.

Impact of time-resolved MRA on diagnostic accuracy in patients with symptomatic peripheral artery disease of the calf station.

PubMed

Hansmann, Jan; Michaely, Henrik J; Morelli, John N; Diehl, Steffen J; Meyer, Mathias; Schoenberg, Stefan O; Attenberger, Ulrike I

2013-12-01

The purpose of this article is to evaluate the added diagnostic accuracy of time-resolved MR angiography (MRA) of the calves compared with continuous-table-movement MRA in patients with symptomatic lower extremity peripheral artery disease (PAD) using digital subtraction angiography (DSA) correlation. Eighty-four consecutive patients with symptomatic PAD underwent a low-dose 3-T MRA protocol, consisting of continuous-table-movement MRA, acquired from the diaphragm to the calves, and an additional time-resolved MRA of the calves; 0.1 mmol/kg body weight (bw) of contrast material was used (0.07 mmol/kg bw for continuous-table-movement MRA and 0.03 mmol/kg bw for time-resolved MRA). Two radiologists rated image quality on a 4-point scale and stenosis degree on a 3-point scale. An additional assessment determined the degree of venous contamination and whether time-resolved MRA improved diagnostic confidence. The accuracy of stenosis gradation with continuous-table-movement and time-resolved MRA was compared with that of DSA as a correlation. Overall diagnostic accuracy was calculated for continuous-table-movement and time-resolved MRA. Median image quality was rated as good for 578 vessel segments with continuous-table-movement MRA and as excellent for 565 vessel segments with time-resolved MRA. Interreader agreement was excellent (κ = 0.80-0.84). Venous contamination interfered with diagnosis in more than 60% of continuous-table-movement MRA examinations. The degree of stenosis was assessed for 340 vessel segments. The diagnostic accuracies (continuous-table-movement MRA/time-resolved MRA) combined for the readers were obtained for the tibioperoneal trunk (84%/93%), anterior tibial (69%/87%), posterior tibial (85%/91%), and peroneal (67%/81%) arteries. The addition of time-resolved MRA improved diagnostic confidence in 69% of examinations. The addition of time-resolved MRA at the calf station improves diagnostic accuracy over continuous-table-movement MRA alone in symptomatic patients with PAD.

Natural mode of horizontal transmission of bovine leukemia virus (BLV): the potential role of tabanids (Tabanus spp.).

PubMed

Manet, G; Guilbert, X; Roux, A; Vuillaume, A; Parodi, A L

1989-10-01

In order to evaluate the potential role of hematophagous insects in the natural spreading of bovine leukemia virus (BLV) infection in cattle, a 2-year survey was carried out involving sequential serological tests on 3328 cattle in three different areas. A parallel entomological study was run over the same period, using continuous trapping, in order to determine both the density and variations of horsefly (Tabanus spp.) populations in the close vicinity of the herds. After statistical analysis, this space-time study showed that: (1) There is a significant positive geographical correlation between the rate of incidence of BLV infection and the density of the horsefly population. (2) Seasonal variations in the incidence rate exist; the highest rates are generally observed during summer (from July of September), and the lowest during winter, spring and early summer (from November to mid-July). (3) There is a time link between the rate of sero-conversion and the variations in activity of the horsefly population. All these data combined would appear to indicate that tabanids play a considerable role in the spread of BLV under natural conditions.

Interest of waiting time for spontaneous early reconnection after cavotricuspid isthmus ablation: A monocentric randomized trial.

PubMed

Marchandise, Sébastien; Scavée, Christophe; Barbraud, Cynthia; de Meester de Ravenstein, Christophe; Balola Bagalwa, Mittérand; Goesaert, Cédric; Reis-Pinheiro, Ivone; le Polain de Waroux, Jean-Benoit

2017-12-01

The aim of this study was to determine the rate of recurrent atrial flutter (AFl) after isolated cavotricuspid isthmus (CTI) ablation and to evaluate the impact of a waiting period with the search for early resumption of the CTI block on the long-term outcome. Three hundred and nineteen consecutive patients referred for typical AFl ablation were randomly assigned to CTI ablation with continuous reevaluation of the CTI block during 30 minutes and early reablation if needed (waiting time [WT] + group, n  =  155) or to CTI ablation with no waiting period after proven bidirectional CTI block (WT - group, n  =  164). All patients were regularly followed-up. In the WT+ group, 10 patients (6%) presented a recovery across the CTI (time to recovery: 17 ± 7') and were reablated at the end of the waiting period. After a median follow-up of 21 months, the rate of recurrent AFl was significantly higher in the WT - group as compared to the WT+ group (11.6% [19/164] vs 2.5% [4/155], respectively; P  =  0.007). However, no significant differences in the subsequent rate of AF were observed between the two groups (29% [WT -] vs 32% [WT+], P  =  0.66). During the follow-up, 28 patients from the WT - group underwent a second ablation procedure (16 AFl redo and 12 AF ablation) versus 10 patients form the WT+ group (three AFl redo and seven AF ablation). Waiting 30 minutes after CTI ablation to check for early resumption and early reablation allows for decreasing significantly the rate of recurrent atrial flutter. © 2017 Wiley Periodicals, Inc.

Influence of operating pressure on the biological hydrogen methanation in trickle-bed reactors.

PubMed

Ullrich, Timo; Lindner, Jonas; Bär, Katharina; Mörs, Friedemann; Graf, Frank; Lemmer, Andreas

2018-01-01

In order to investigate the influence of pressures up to 9bar absolute on the productivity of trickle-bed reactors for biological methanation of hydrogen and carbon dioxide, experiments were carried out in a continuously operated experimental plant with three identical reactors. The pressure increase promises a longer residence time and improved mass transfer of H 2 due to higher gas partial pressures. The study covers effects of different pressures on important parameters like gas hourly space velocity, methane formation rate, conversion rates and product gas quality. The methane content of 64.13±3.81vol-% at 1.5bar could be increased up to 86.51±0.49vol-% by raising the pressure to 9bar. Methane formation rates of up to 4.28±0.26m 3 m -3 d -1 were achieved. Thus, pressure increase could significantly improve reactor performance. Copyright © 2017 Elsevier Ltd. All rights reserved.

State-space self-tuner for on-line adaptive control

NASA Technical Reports Server (NTRS)

Shieh, L. S.

1994-01-01

Dynamic systems, such as flight vehicles, satellites and space stations, operating in real environments, constantly face parameter and/or structural variations owing to nonlinear behavior of actuators, failure of sensors, changes in operating conditions, disturbances acting on the system, etc. In the past three decades, adaptive control has been shown to be effective in dealing with dynamic systems in the presence of parameter uncertainties, structural perturbations, random disturbances and environmental variations. Among the existing adaptive control methodologies, the state-space self-tuning control methods, initially proposed by us, are shown to be effective in designing advanced adaptive controllers for multivariable systems. In our approaches, we have embedded the standard Kalman state-estimation algorithm into an online parameter estimation algorithm. Thus, the advanced state-feedback controllers can be easily established for digital adaptive control of continuous-time stochastic multivariable systems. A state-space self-tuner for a general multivariable stochastic system has been developed and successfully applied to the space station for on-line adaptive control. Also, a technique for multistage design of an optimal momentum management controller for the space station has been developed and reported in. Moreover, we have successfully developed various digital redesign techniques which can convert a continuous-time controller to an equivalent digital controller. As a result, the expensive and unreliable continuous-time controller can be implemented using low-cost and high performance microprocessors. Recently, we have developed a new hybrid state-space self tuner using a new dual-rate sampling scheme for on-line adaptive control of continuous-time uncertain systems.

Fast packet switching algorithms for dynamic resource control over ATM networks

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

Tsang, R.P.; Keattihananant, P.; Chang, T.

1996-12-01

Real-time continuous media traffic, such as digital video and audio, is expected to comprise a large percentage of the network load on future high speed packet switch networks such as ATM. A major feature which distinguishes high speed networks from traditional slower speed networks is the large amount of data the network must process very quickly. For efficient network usage, traffic control mechanisms are essential. Currently, most mechanisms for traffic control (such as flow control) have centered on the support of Available Bit Rate (ABR), i.e., non real-time, traffic. With regard to ATM, for ABR traffic, two major types ofmore » schemes which have been proposed are rate- control and credit-control schemes. Neither of these schemes are directly applicable to Real-time Variable Bit Rate (VBR) traffic such as continuous media traffic. Traffic control for continuous media traffic is an inherently difficult problem due to the time- sensitive nature of the traffic and its unpredictable burstiness. In this study, we present a scheme which controls traffic by dynamically allocating/de- allocating resources among competing VCs based upon their real-time requirements. This scheme incorporates a form of rate- control, real-time burst-level scheduling and link-link flow control. We show analytically potential performance improvements of our rate- control scheme and present a scheme for buffer dimensioning. We also present simulation results of our schemes and discuss the tradeoffs inherent in maintaining high network utilization and statistically guaranteeing many users` Quality of Service.« less

An Indirect System Identification Technique for Stable Estimation of Continuous-Time Parameters of the Vestibulo-Ocular Reflex (VOR)

NASA Technical Reports Server (NTRS)

Kukreja, Sunil L.; Wallin, Ragnar; Boyle, Richard D.

2013-01-01

The vestibulo-ocular reflex (VOR) is a well-known dual mode bifurcating system that consists of slow and fast modes associated with nystagmus and saccade, respectively. Estimation of continuous-time parameters of nystagmus and saccade models are known to be sensitive to estimation methodology, noise and sampling rate. The stable and accurate estimation of these parameters are critical for accurate disease modelling, clinical diagnosis, robotic control strategies, mission planning for space exploration and pilot safety, etc. This paper presents a novel indirect system identification method for the estimation of continuous-time parameters of VOR employing standardised least-squares with dual sampling rates in a sparse structure. This approach permits the stable and simultaneous estimation of both nystagmus and saccade data. The efficacy of this approach is demonstrated via simulation of a continuous-time model of VOR with typical parameters found in clinical studies and in the presence of output additive noise.

Crafting the TALE: construction of a measure to assess the functions of autobiographical remembering.

PubMed

Bluck, Susan; Alea, Nicole

2011-07-01

Theory suggests that autobiographical remembering serves several functions. This research builds on previous empirical efforts (Bluck, Alea, Habermas, & Rubin, 2005) with the aim of constructing a brief, valid measure of three functions of autobiographical memory. Participants (N=306) completed 28 theoretically derived items concerning the frequency with which they use autobiographical memory to serve a variety of functions. To examine convergent and discriminant validity, participants rated their tendency to think about and talk about the past, and measures of future time orientation, self-concept clarity, and trait personality. Confirmatory factor analysis of the function items resulted in a respecified model with 15 items in three factors. The newly developed Thinking about Life Experiences scale (TALE) shows good internal consistency as well as convergent validity for three subscales: Self-Continuity, Social-Bonding, and Directing-Behaviour. Analyses demonstrate factorial equivalence across age and gender groups. Potential use and limitations of the TALE are discussed.

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

Chen, Chuchu, E-mail: chenchuchu@lsec.cc.ac.cn; Hong, Jialin, E-mail: hjl@lsec.cc.ac.cn; Zhang, Liying, E-mail: lyzhang@lsec.cc.ac.cn

Stochastic Maxwell equations with additive noise are a system of stochastic Hamiltonian partial differential equations intrinsically, possessing the stochastic multi-symplectic conservation law. It is shown that the averaged energy increases linearly with respect to the evolution of time and the flow of stochastic Maxwell equations with additive noise preserves the divergence in the sense of expectation. Moreover, we propose three novel stochastic multi-symplectic methods to discretize stochastic Maxwell equations in order to investigate the preservation of these properties numerically. We make theoretical discussions and comparisons on all of the three methods to observe that all of them preserve the correspondingmore » discrete version of the averaged divergence. Meanwhile, we obtain the corresponding dissipative property of the discrete averaged energy satisfied by each method. Especially, the evolution rates of the averaged energies for all of the three methods are derived which are in accordance with the continuous case. Numerical experiments are performed to verify our theoretical results.« less

Three-Dimensional Structure and Energy Balance of a Coronal Mass Ejection

NASA Technical Reports Server (NTRS)

Lee, J.-Y.; Raymond, J. C.; Ko, Y.-K.; Kim, K.-S.

2009-01-01

UVCS observed Doppler-shifted material of a partial halo coronal mass ejection (CME) on 2001 December 13. The observed ratio of [O VJ/O V] is a reliable density diagnostic important for assessing the state of the plasma. Earlier UVCS observations of CMEs found evidence that the ejected plasma is heated long after the eruption. This paper investigated the heating rates, which represent a significant fraction of the CME energy budget. The parameterized heating and radiative and adiabatic cooling have been used to evaluate the temperature evolution of the CME material with a time-dependent ionization state model. Continuous heating is required to match the UVCS observations. To match the O VI bright knots, a higher heating rate is required such that the heating energy is greater than the kinetic energy.

Predictive Validity of a Continuous Alternative to Nominal Subtypes of Attention-Deficit Hyperactivity Disorder for DSM-V

PubMed Central

Lahey, Benjamin B.; Willcutt, Erik G.

2010-01-01

Three subtypes of attention-deficit/hyperactivity disorder (ADHD) based on numbers of symptoms of inattention (I) and hyperactivity-impulsivity (HI) were defined in DSM-IV to reduce heterogeneity of the disorder, but the subtypes proved to be highly unstable over time. A continuous alternative to nominal subtyping is evaluated in a longitudinal study of 129 4–6 year old children with ADHD and 130 comparison children. Children who met criteria for all subtypes in year 1 continued to exhibit greater functional impairment than comparison children during years 2–9. Among children with ADHD in year 1, I and HI symptoms differentially predicted teacher-rated need for treatment and reading and mathematics achievement scores over the next 8 years in controlled analyses. Consistent with other studies, these findings suggest that the use of diagnostic modifiers specifying the numbers of I and HI symptoms could reduce heterogeneity and facilitate clinical intervention, prognosis, and research. PMID:21058124

Predictive validity of a continuous alternative to nominal subtypes of attention-deficit/hyperactivity disorder for DSM-V.

PubMed

Lahey, Benjamin B; Willcutt, Erik G

2010-01-01

Three subtypes of attention-deficit/hyperactivity disorder (ADHD) based on numbers of symptoms of inattention (I) and hyperactivity-impulsivity (HI) were defined in the Diagnostic and Statistical Manual of Mental Disorders (4th ed.) to reduce heterogeneity of the disorder, but the subtypes proved to be highly unstable over time. A continuous alternative to nominal subtyping is evaluated in a longitudinal study of 129 four- to six-year-old children with ADHD and 130 comparison children. Children who met criteria for all subtypes in Year 1 continued to exhibit greater functional impairment than comparison children during Years 2 to 9. Among children with ADHD in Year 1, I and HI symptoms differentially predicted teacher-rated need for treatment and reading and mathematics achievement scores over the next 8 years in controlled analyses. Consistent with other studies, these findings suggest that the use of diagnostic modifiers specifying the numbers of I and HI symptoms could reduce heterogeneity and facilitate clinical intervention, prognosis, and research.

A Longitudinal Investigation of Predictors of the Association Between Age 3 and Age 6 Behavioural Inhibition

PubMed Central

Johnson, Victoria C.; Olino, Thomas M.; Klein, Daniel N.; Dyson, Margaret W.; Bufferd, Sara J.; Durbin, C. Emily; Dougherty, Lea R.; Hayden, Elizabeth P.

2016-01-01

Children who exhibit elevated levels of the temperament trait behavioural inhibition (BI) across time may be at greatest risk for anxiety. However, little research has investigated the influence of other temperamental traits, particularly positive emotionality (PE), on the continuity of BI in childhood, nor whether parental overprotection influences associations between early and later child BI. To explore whether PE and overprotection shape associations between early and later BI, this longitudinal study of three-year-olds (N = 446) followed up at age 6 included tasks tapping child temperament, and parental overprotection was assessed via interview ratings and parent-report. Lower levels of child PE and higher levels of caregiver overprotection at baseline predicted stronger associations between laboratory-assessed BI at ages 3 and 6. Findings elucidate influences shaping the developmental continuity of BI. PMID:27765998

A Longitudinal Investigation of Predictors of the Association Between Age 3 and Age 6 Behavioural Inhibition.

PubMed

Johnson, Victoria C; Olino, Thomas M; Klein, Daniel N; Dyson, Margaret W; Bufferd, Sara J; Durbin, C Emily; Dougherty, Lea R; Hayden, Elizabeth P

2016-08-01

Children who exhibit elevated levels of the temperament trait behavioural inhibition (BI) across time may be at greatest risk for anxiety. However, little research has investigated the influence of other temperamental traits, particularly positive emotionality (PE), on the continuity of BI in childhood, nor whether parental overprotection influences associations between early and later child BI. To explore whether PE and overprotection shape associations between early and later BI, this longitudinal study of three-year-olds ( N = 446) followed up at age 6 included tasks tapping child temperament, and parental overprotection was assessed via interview ratings and parent-report. Lower levels of child PE and higher levels of caregiver overprotection at baseline predicted stronger associations between laboratory-assessed BI at ages 3 and 6. Findings elucidate influences shaping the developmental continuity of BI.

38 CFR 21.3131 - Rates-educational assistance allowance-38 U.S.C. chapter 35.

Code of Federal Regulations, 2010 CFR

2010-07-01

... DEPARTMENT OF VETERANS AFFAIRS (CONTINUED) VOCATIONAL REHABILITATION AND EDUCATION Survivors' and Dependents... June 30, 2004, and before October 1, 2004: Type of course Monthly rate Institutional: Full time $788.00... September 30, 2004, and before October 1, 2005: Type of course Monthly rate Institutional: Full time $803.00...

Movement patterns and the medium-sized city. Tenants on the move in Gweru, Zimbabwe.

PubMed

Grant, M

1995-01-01

During 1965-79, urban growth rates accelerated and continued after Zimbabwe's independence in 1980. For 1960-80, the estimated urban growth rate was 5.6% as compared with the natural growth rate of 3.5% and urban growth rate of 5.0% to 8.1% for the period 1982-92. Gweru, Zimbabwe, had a population of 110,000 in 1990, and as the provincial capital it is an important destination for rural and interurban migrants. Between 1982 and 1990 there was a 4.9% growth rate, resulting in the municipal waiting list for housing to exceed 14,000 in mid-1990. In a large study on migration and rental shelter, 188 tenants were interviewed in high, low-medium density, and periurban areas of the city with the intent of tracing respondents and the nature of migration streams. Regarding origins and connections, only one-fifth of the migrants were born in Gweru, more than half were born in rural areas, and the rest in other urban areas. More than 90% still had rural homes. Two-thirds made rural home visits six times or less a year and one-fourth visited seven times a year to once a month. 40% of the migrants to Gweru originated in larger cities, 24% in smaller urban areas, and 36% in rural areas. 58% moved to high density areas, 34% to low-medium, and 8% to peri-urban areas. The dominant motive was the search for employment and direct transfers, thus economic factors dominated over social factors. Three groups were distinguished according to length of stay: 1) 5 years or less who lived mainly in high and low-medium density housing; 2) 6-15 years; and 3) more than 15 years who lived in low density and high density areas. Regarding the previous two migrations, two-thirds stayed at the previous place for 5 years of less. The reasons for migration were overcrowding, family, and employment. Within Gweru high mobility was typical: one-third initiated one step, 43% initiated two steps, and 27% initiated three steps. Lodgers were the most mobile since one-third were moving three times.

Creep of plasma sprayed zirconia

NASA Technical Reports Server (NTRS)

Firestone, R. F.; Logan, W. R.; Adams, J. W.

1982-01-01

Specimens of plasma-sprayed zirconia thermal barrier coatings with three different porosities and different initial particle sizes were deformed in compression at initial loads of 1000, 2000, and 3500 psi and temperatures of 1100 C, 1250 C, and 1400 C. The coatings were stabilized with lime, magnesia, and two different concentrations of yttria. Creep began as soon as the load was applied and continued at a constantly decreasing rate until the load was removed. Temperature and stabilization had a pronounced effect on creep rate. The creep rate for 20% Y2O3-80% ZrO2 was 1/3 to 1/2 that of 8% Y2O3-92% ZrO2. Both magnesia and calcia stabilized ZrO2 crept at a rate 5 to 10 times that of the 20% Y2O3 material. A near proportionality between creep rate and applied stress was observed. The rate controlling process appeared to be thermally activated, with an activation energy of approximately 100 cal/gm mole K. Creep deformation was due to cracking and particle sliding.

Optimally setting up directed searches for continuous gravitational waves in Advanced LIGO O1 data

NASA Astrophysics Data System (ADS)

Ming, Jing; Papa, Maria Alessandra; Krishnan, Badri; Prix, Reinhard; Beer, Christian; Zhu, Sylvia J.; Eggenstein, Heinz-Bernd; Bock, Oliver; Machenschalk, Bernd

2018-02-01

In this paper we design a search for continuous gravitational waves from three supernova remnants: Vela Jr., Cassiopeia A (Cas A) and G347.3. These systems might harbor rapidly rotating neutron stars emitting quasiperiodic gravitational radiation detectable by the advanced LIGO detectors. Our search is designed to use the volunteer computing project Einstein@Home for a few months and assumes the sensitivity and duty cycles of the advanced LIGO detectors during their first science run. For all three supernova remnants, the sky positions of their central compact objects are well known but the frequency and spin-down rates of the neutron stars are unknown which makes the searches computationally limited. In a previous paper we have proposed a general framework for deciding on what target we should spend computational resources and in what proportion, what frequency and spin-down ranges we should search for every target, and with what search setup. Here we further expand this framework and apply it to design a search directed at detecting continuous gravitational wave signals from the most promising three supernova remnants identified as such in the previous work. Our optimization procedure yields broad frequency and spin-down searches for all three objects, at an unprecedented level of sensitivity: The smallest detectable gravitational wave strain h0 for Cas A is expected to be 2 times smaller than the most sensitive upper limits published to date, and our proposed search, which was set up and ran on the volunteer computing project Einstein@Home, covers a much larger frequency range.

Systematic design and three-dimensional simulation of X-ray FEL oscillator for Shanghai Coherent Light Facility

NASA Astrophysics Data System (ADS)

Li, Kai; Deng, Haixiao

2018-07-01

The Shanghai Coherent Light Facility (SCLF) is a quasi-continuous wave hard X-ray free electron laser facility, which is currently under construction. Due to the high repetition rate and high-quality electron beams, it is straightforward to consider X-ray free electron laser oscillator (XFELO) operation for the SCLF. In this paper, the main processes for XFELO design, and parameter optimization of the undulator, X-ray cavity, and electron beam are described. A three-dimensional X-ray crystal Bragg diffraction code, named BRIGHT, was introduced for the first time, which can be combined with the GENESIS and OPC codes for the numerical simulations of the XFELO. The performance of the XFELO of the SCLF is investigated and optimized by theoretical analysis and numerical simulation.

Typewriting rate as a function of reaction time.

PubMed

Hayes, V; Wilson, G D; Schafer, R L

1977-12-01

This study was designed to determine the relationship between reaction time and typewriting rate. Subjects were 24 typists ranging in age from 19 to 39 yr. Reaction times (.001 sec) to a light were recorded for each finger and to each alphabetic character and three punctuation marks. Analysis of variance yielded significant differences in reaction time among subjects and fingers. Correlation between typewriting rate and average reaction time to the alphabetic characters and three punctuation marks was --.75. Correlation between typewriting rate and the difference between the reaction time of the hands was --.42. Factors influencing typewriting rate may include reaction time of the fingers, difference between the reaction time of the hands, and reaction time to individual keys on the typewriter. Implications exist for instructional methodology and further research.

Procedure for calculating estimated ultimate recoveries of Bakken and Three Forks Formations horizontal wells in the Williston Basin

USGS Publications Warehouse

Cook, Troy A.

2013-01-01

Estimated ultimate recoveries (EURs) are a key component in determining productivity of wells in continuous-type oil and gas reservoirs. EURs form the foundation of a well-performance-based assessment methodology initially developed by the U.S. Geological Survey (USGS; Schmoker, 1999). This methodology was formally reviewed by the American Association of Petroleum Geologists Committee on Resource Evaluation (Curtis and others, 2001). The EUR estimation methodology described in this paper was used in the 2013 USGS assessment of continuous oil resources in the Bakken and Three Forks Formations and incorporates uncertainties that would not normally be included in a basic decline-curve calculation. These uncertainties relate to (1) the mean time before failure of the entire well-production system (excluding economics), (2) the uncertainty of when (and if) a stable hyperbolic-decline profile is revealed in the production data, (3) the particular formation involved, (4) relations between initial production rates and a stable hyperbolic-decline profile, and (5) the final behavior of the decline extrapolation as production becomes more dependent on matrix storage.

Conversion of spin current into charge current in a topological insulator: Role of the interface

NASA Astrophysics Data System (ADS)

Dey, Rik; Prasad, Nitin; Register, Leonard F.; Banerjee, Sanjay K.

2018-05-01

Three-dimensional spin current density injected onto the surface of a topological insulator (TI) produces a two-dimensional charge current density on the surface of the TI, which is the so-called inverse Edelstein effect (IEE). The ratio of the surface charge current density on the TI to the spin current density injected across the interface defined as the IEE length was shown to be exactly equal to the mean free path in the TI determined to be independent of the electron transmission rate across the interface [Phys. Rev. B 94, 184423 (2016), 10.1103/PhysRevB.94.184423]. However, we find that the transmission rate across the interface gives a nonzero contribution to the transport relaxation rate in the TI as well as to the effective IEE relaxation rate (over and above any surface hybridization effects), and the IEE length is always less than the original mean free path in the TI without the interface. We show that both the IEE relaxation time and the transport relaxation time in the TI are modified by the interface transmission time. The correction becomes significant when the transmission time across the interface becomes comparable to or less than the original momentum scattering time in the TI. This correction is similar to experimental results in Rashba electron systems in which the IEE relaxation time was found shorter in the case of direct interface with metal in which the interface transmission rate will be much higher, compared to interfaces incorporating insulating oxides. Our results indicate the continued importance of the interface to obtain a better spin-to-charge current conversion and a limitation to the conversion efficiency due to the quality of the interface.

In-situ biofouling of ocean thermal energy conversion (OTEC) evaporator tubes

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

Sasscer, D.S.; Morgan, T.

1981-05-01

The Puerto Rico Center for Energy and Environmental Research equipped a LCU facility in 1100 m of water near Punta Tuna, Puerto Rico to measure in situ biofouling of simulated Ocean Thermal Energy Conversion evaporator tubes. The system consisted of two 5052 aluminum alloy and two titanium tubes, through which a continuous flow of ocean water was maintained. The tubes were cleaned three times and the fouling resistance was measured, showing only slight differences between the tubes with respect to heat transfer loss resulting from biofouling. In all units, the average fouling rate after cleaning was greater than before cleaning,more » and only after the first cleaning did the aluminum units show greater fouling rates than did the titanium. The titanium units showed a progressive increase in the fouling rates with each cleaning. The subsequent average fouling rates for all units after eight months were between 4 and 4.6 x 0.000010 sq m-k/W-day.« less

Study to determine potential flight applications and human factors design guidelines for voice recognition and synthesis systems

NASA Astrophysics Data System (ADS)

White, R. W.; Parks, D. L.

1985-07-01

A study was conducted to determine potential commercial aircraft flight deck applications and implementation guidelines for voice recognition and synthesis. At first, a survey of voice recognition and synthesis technology was undertaken to develop a working knowledge base. Then, numerous potential aircraft and simulator flight deck voice applications were identified and each proposed application was rated on a number of criteria in order to achieve an overall payoff rating. The potential voice recognition applications fell into five general categories: programming, interrogation, data entry, switch and mode selection, and continuous/time-critical action control. The ratings of the first three categories showed the most promise of being beneficial to flight deck operations. Possible applications of voice synthesis systems were categorized as automatic or pilot selectable and many were rated as being potentially beneficial. In addition, voice system implementation guidelines and pertinent performance criteria are proposed. Finally, the findings of this study are compared with those made in a recent NASA study of a 1995 transport concept.

Polar organic chemical integrative sampler (POCIS) uptake rates for 17 polar pesticides and degradation products: laboratory calibration.

PubMed

Ibrahim, Imtiaz; Togola, Anne; Gonzalez, Catherine

2013-06-01

Polar organic chemical integrative samplers (POCIS) are useful for monitoring a wide range of chemicals, including polar pesticides, in water bodies. However, few calibration data are available, which limits the use of these samplers for time-weighted average concentration measurements in an aquatic medium. This work deals with the laboratory calibration of the pharmaceutical configuration of a polar organic chemical integrative sampler (pharm-POCIS) for calculating the sampling rates of 17 polar pesticides (1.15 ≤  logK(ow) ≤ 3.71) commonly found in water. The experiment, conducted for 21 days in a continuous water flow-through exposure system, showed an integrative accumulation of all studied pesticides for 15 days. Three compounds (metalaxyl, azoxystrobine, and terbuthylazine) remained integrative for the 21-day experiment. The sampling rates measured ranged from 67.9 to 279 mL day(-1) and increased with the hydrophobicity of the pesticides until reaching a plateau where no significant variation in sampling rate is observed when increasing the hydrophobicity.

Study to determine potential flight applications and human factors design guidelines for voice recognition and synthesis systems

NASA Technical Reports Server (NTRS)

White, R. W.; Parks, D. L.

1985-01-01

A study was conducted to determine potential commercial aircraft flight deck applications and implementation guidelines for voice recognition and synthesis. At first, a survey of voice recognition and synthesis technology was undertaken to develop a working knowledge base. Then, numerous potential aircraft and simulator flight deck voice applications were identified and each proposed application was rated on a number of criteria in order to achieve an overall payoff rating. The potential voice recognition applications fell into five general categories: programming, interrogation, data entry, switch and mode selection, and continuous/time-critical action control. The ratings of the first three categories showed the most promise of being beneficial to flight deck operations. Possible applications of voice synthesis systems were categorized as automatic or pilot selectable and many were rated as being potentially beneficial. In addition, voice system implementation guidelines and pertinent performance criteria are proposed. Finally, the findings of this study are compared with those made in a recent NASA study of a 1995 transport concept.

Simulation platform of LEO satellite communication system based on OPNET

NASA Astrophysics Data System (ADS)

Zhang, Yu; Zhang, Yong; Li, Xiaozhuo; Wang, Chuqiao; Li, Haihao

2018-02-01

For the purpose of verifying communication protocol in the low earth orbit (LEO) satellite communication system, an Optimized Network Engineering Tool (OPNET) based simulation platform is built. Using the three-layer modeling mechanism, the network model, the node model and the process model of the satellite communication system are built respectively from top to bottom, and the protocol will be implemented by finite state machine and Proto-C language. According to satellite orbit parameters, orbit files are generated via Satellite Tool Kit (STK) and imported into OPNET, and the satellite nodes move along their orbits. The simulation platform adopts time-slot-driven mode, divides simulation time into continuous time slots, and allocates slot number for each time slot. A resource allocation strategy is simulated on this platform, and the simulation results such as resource utilization rate, system throughput and packet delay are analyzed, which indicate that this simulation platform has outstanding versatility.

Factors Influencing Retention Among Part-Time Clinical Nursing Faculty.

PubMed

Carlson, Joanne S

This study sought to determine job characteristics influencing retention of part-time clinical nurse faculty teaching in pre-licensure nursing education. Large numbers of part-time faculty are needed to educate students in the clinical setting. Faculty retention helps maintain consistency and may positively influence student learning. A national sample of part-time clinical nurse faculty teaching in baccalaureate programs responded to a web-based survey. Respondents were asked to identify the primary reason for wanting or not wanting to continue working for a school of nursing (SON). Affinity for students, pay and benefits, support, and feeling valued were the top three reasons given for continuing to work at an SON. Conflicts with life and other job responsibilities, low pay, and workload were the top three reasons given for not continuing. Results from this study can assist nursing programs in finding strategies to help reduce attrition among part-time clinical faculty.

Oregon's On-Time High School Graduation Rate Shows Strong Growth in 2014-15. Research Brief

ERIC Educational Resources Information Center

Oregon Department of Education, 2016

2016-01-01

Oregon continues to make gains in its on-time high school graduation rate. The rate increased to 74% for the 2014-15 school year--up from 72% the year before. The graduation rate for almost all student groups rose, led by Hispanic students (2.4 percentage points) and Black students (2.4 percentage points). The rate for economically disadvantaged…

Change over time in parents' beliefs about and reported use of corporal punishment in eight countries with and without legal bans.

PubMed

Lansford, Jennifer E; Cappa, Claudia; Putnick, Diane L; Bornstein, Marc H; Deater-Deckard, Kirby; Bradley, Robert H

2017-09-01

Stopping violence against children is prioritized in goal 16 of the Sustainable Development Goals adopted by the United Nations General Assembly in 2015. All forms of child corporal punishment have been outlawed in 50 countries as of October 2016. Using data from 56,371 caregivers in eight countries that participated in UNICEF's Multiple Indicator Cluster Survey, we examined change from Time 1 (2005-6) to Time 2 (2008-13) in national rates of corporal punishment of 2- to 14-year-old children and in caregivers' beliefs regarding the necessity of using corporal punishment. One of the participating countries outlawed corporal punishment prior to Time 1 (Ukraine), one outlawed corporal punishment between Times 1 and 2 (Togo), two outlawed corporal punishment after Time 2 (Albania and Macedonia), and four have not outlawed corporal punishment as of 2016 (Central African Republic, Kazakhstan, Montenegro, and Sierra Leone). Rates of reported use of corporal punishment and belief in its necessity decreased over time in three countries; rates of reported use of severe corporal punishment decreased in four countries. Continuing use of corporal punishment and belief in the necessity of its use in some countries despite legal bans suggest that campaigns to promote awareness of legal bans and to educate parents regarding alternate forms of discipline are worthy of international attention and effort along with legal bans themselves. Copyright © 2016 Elsevier Ltd. All rights reserved.

Continuous direct tablet compression: effects of impeller rotation rate, total feed rate and drug content on the tablet properties and drug release.

PubMed

Järvinen, Maiju A; Paaso, Janne; Paavola, Marko; Leiviskä, Kauko; Juuti, Mikko; Muzzio, Fernando; Järvinen, Kristiina

2013-11-01

Continuous processing is becoming popular in the pharmaceutical industry for its cost and quality advantages. This study evaluated the mechanical properties, uniformity of dosage units and drug release from the tablets prepared by continuous direct compression process. The tablet formulations consisted of acetaminophen (3-30% (w/w)) pre-blended with 0.25% (w/w) colloidal silicon dioxide, microcrystalline cellulose (69-96% (w/w)) and magnesium stearate (1% (w/w)). The continuous tableting line consisted of three loss-in-weight feeders and a convective continuous mixer and a rotary tablet press. The process continued for 8 min and steady state was reached within 5 min. The effects of acetaminophen content, impeller rotation rate (39-254 rpm) and total feed rate (15 and 20 kg/h) on tablet properties were examined. All the tablets complied with the friability requirements of European Pharmacopoeia and rapidly released acetaminophen. However, the relative standard deviation of acetaminophen content (10% (w/w)) increased with an increase in impeller rotation rate at a constant total feed rate (20 kg/h). A compression force of 12 kN tended to result in greater tablet hardness and subsequently a slower initial acetaminophen release from tablets when compared with those made with the compression force of about 8 kN. In conclusion, tablets could be successfully prepared by a continuous direct compression process and process conditions affected to some extent tablet properties.

A hybrid-system model of the coagulation cascade: simulation, sensitivity, and validation.

PubMed

Makin, Joseph G; Narayanan, Srini

2013-10-01

The process of human blood clotting involves a complex interaction of continuous-time/continuous-state processes and discrete-event/discrete-state phenomena, where the former comprise the various chemical rate equations and the latter comprise both threshold-limited behaviors and binary states (presence/absence of a chemical). Whereas previous blood-clotting models used only continuous dynamics and perforce addressed only portions of the coagulation cascade, we capture both continuous and discrete aspects by modeling it as a hybrid dynamical system. The model was implemented as a hybrid Petri net, a graphical modeling language that extends ordinary Petri nets to cover continuous quantities and continuous-time flows. The primary focus is simulation: (1) fidelity to the clinical data in terms of clotting-factor concentrations and elapsed time; (2) reproduction of known clotting pathologies; and (3) fine-grained predictions which may be used to refine clinical understanding of blood clotting. Next we examine sensitivity to rate-constant perturbation. Finally, we propose a method for titrating between reliance on the model and on prior clinical knowledge. For simplicity, we confine these last two analyses to a critical purely-continuous subsystem of the model.

Determining the ventilation and aerosol deposition rates from routine indoor-air measurements.

PubMed

Halios, Christos H; Helmis, Costas G; Deligianni, Katerina; Vratolis, Sterios; Eleftheriadis, Konstantinos

2014-01-01

Measurement of air exchange rate provides critical information in energy and indoor-air quality studies. Continuous measurement of ventilation rates is a rather costly exercise and requires specific instrumentation. In this work, an alternative methodology is proposed and tested, where the air exchange rate is calculated by utilizing indoor and outdoor routine measurements of a common pollutant such as SO2, whereas the uncertainties induced in the calculations are analytically determined. The application of this methodology is demonstrated, for three residential microenvironments in Athens, Greece, and the results are also compared against ventilation rates calculated from differential pressure measurements. The calculated time resolved ventilation rates were applied to the mass balance equation to estimate the particle loss rate which was found to agree with literature values at an average of 0.50 h(-1). The proposed method was further evaluated by applying a mass balance numerical model for the calculation of the indoor aerosol number concentrations, using the previously calculated ventilation rate, the outdoor measured number concentrations and the particle loss rates as input values. The model results for the indoors' concentrations were found to be compared well with the experimentally measured values.

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.

Hybrid suboptimal control of multi-rate multi-loop sampled-data systems

NASA Technical Reports Server (NTRS)

Shieh, Leang S.; Chen, Gwangchywan; Tsai, Jason S. H.

1992-01-01

A hybrid state-space controller is developed for suboptimal digital control of multirate multiloop multivariable continuous-time systems. First, an LQR is designed for a continuous-time subsystem which has a large bandwidth and is connnected in the inner loop of the overall system. The designed LQR would optimally place the eigenvalues of a closed-loop subsystem in the common region of an open sector bounded by sector angles + or - pi/2k for k = 2 or 3 from the negative real axis and the left-hand side of a vertical line on the negative real axis in the s-plane. Then, the developed continuous-time state-feedback gain is converted into an equivalent fast-rate discrete-time state-feedback gain via a digital redesign technique (Tsai et al. 1989, Shieh et al. 1990) reviewed here. A real state reconstructor is redeveloped utilizing the fast-rate input-output data of the system of interest. The design procedure of multiloop multivariable systems using multirate samplers is shown, and a terminal homing missile system example is used to demonstrate the effectiveness of the proposed method.

Space-to-Space Communications System

NASA Technical Reports Server (NTRS)

Tu, Kwei; Gaylor, Kent; Vitalpur, Sharada; Sham, Cathy

1999-01-01

The Space-to-Space Communications System (SSCS) is an Ultra High Frequency (UHF) Time-Division-Multiple Access (TDMA) system that is designed, developed, and deployed by the NASA Johnson Space Center (JSC) to provide voice, commands, telemetry and data services in close proximity among three space elements: International Space Station (ISS), Space Shuttle Orbiter, and Extravehicular Mobility Units (EMU). The SSCS consists of a family of three radios which are, Space-to-Space Station Radio (SSSR), Space-to-Space Orbiter Radio (SSOR), and Space-to-Space Extravehicular Mobility Radio (SSER). The SSCS can support up to five such radios at a time. Each user has its own time slot within which to transmit voice and data. Continuous Phase Frequency Shift Keying (CPFSK) carrier modulation with a burst data rate of 695 kbps and a frequency deviation of 486.5 kHz is employed by the system. Reed-Solomon (R-S) coding is also adopted to ensure data quality. In this paper, the SSCS system requirements, operational scenario, detailed system architecture and parameters, link acquisition strategy, and link performance analysis will be presented and discussed

Co-movement of Africa's equity markets: Regional and global analysis in the frequency-time domains

NASA Astrophysics Data System (ADS)

Boako, Gideon; Alagidede, Paul

2017-02-01

This paper examines regional and global co-movement of Africa's stock markets using the three-dimensional continuous Morlet wavelet transform methodology. The analyses which are done in segments investigate co-movements with global markets; bilateral exchange rates expressed in US dollars and euro; and four regional markets in Africa. First, we find evidence of stronger co-movements broadly narrowed to short-run fluctuations. The co-movements are time-varying and commonly non-homogeneous - with phase difference arrow vectors implying lead-lag relationships. The presence of lead-lag effects and stronger co-movements at short-run fluctuations may induce arbitrage and diversification opportunities to both local and international investors with long-term investment horizons. The findings also reveal that some African equity markets are, to a degree, segmented from volatilities of the dollar and euro exchange rates. Thus, inferring that, ceteris paribus, international investors may diversify their portfolio investments across those markets without worrying about the effects of currency price volatility.

Shortened lengths of stay: ensuring continuity of care for mothers and babies.

PubMed

Welsh, C; Ludwig-Beymer, P

1998-01-01

Hospital discharge on the day after an uncomplicated vaginal delivery may be appropriate if clinical criteria are used for the selection of patients and post-discharge follow-up plans are in place. To ensure safety for these patients, Advocate Health Care developed a mother/baby philosophy statement, guidelines for maternal and infant discharge in less than 48 hours, and an algorithm to assure that appropriate follow-up care takes place after discharge. To evaluate the Mother/Baby Home Transition Program, home health follow up, readmission rates, and sentinel events were tracked. Most home health visits occurred within 48 hours. Infant readmission rates ranged from 1.1-2.6%, whereas maternal readmission rates ranged from 0-0.52%. Three sentinel events in 1996 and three in 1997 required readmissions to an ICU. Data continue to be monitored and shared monthly with clinical leaders.

Evaluating the impact of a mandatory pre-abortion ultrasound viewing law: A mixed methods study.

PubMed

Upadhyay, Ushma D; Kimport, Katrina; Belusa, Elise K O; Johns, Nicole E; Laube, Douglas W; Roberts, Sarah C M

2017-01-01

Since mid-2013, Wisconsin abortion providers have been legally required to display and describe pre-abortion ultrasound images. We aimed to understand the impact of this law. We used a mixed-methods study design at an abortion facility in Wisconsin. We abstracted data from medical charts one year before the law to one year after and used multivariable models, mediation/moderation analysis, and interrupted time series to assess the impact of the law, viewing, and decision certainty on likelihood of continuing the pregnancy. We conducted in-depth interviews with women in the post-law period about their ultrasound experience and analyzed them using elaborative and modified grounded theory. A total of 5342 charts were abstracted; 8.7% continued their pregnancies pre-law and 11.2% post-law (p = 0.002). A multivariable model confirmed the law was associated with higher odds of continuing pregnancy (aOR = 1.23, 95% CI: 1.01-1.50). Decision certainty (aOR = 6.39, 95% CI: 4.72-8.64) and having to pay fully out of pocket (aOR = 4.98, 95% CI: 3.86-6.41) were most strongly associated with continuing pregnancy. Ultrasound viewing fully mediated the relationship between the law and continuing pregnancy. Interrupted time series analyses found no significant effect of the law but may have been underpowered to detect such a small effect. Nineteen of twenty-three women interviewed viewed their ultrasound image. Most reported no impact on their abortion decision; five reported a temporary emotional impact or increased certainty about choosing abortion. Two women reported that viewing helped them decide to continue the pregnancy; both also described preexisting decision uncertainty. This law caused an increase in viewing rates and a statistically significant but small increase in continuing pregnancy rates. However, the majority of women were certain of their abortion decision and the law did not change their decision. Other factors were more significant in women's decision-making, suggesting evaluations of restrictive laws should take account of the broader social environment.

Evaluating the impact of a mandatory pre-abortion ultrasound viewing law: A mixed methods study

PubMed Central

Kimport, Katrina; Belusa, Elise K. O.; Johns, Nicole E.; Laube, Douglas W.; Roberts, Sarah C. M.

2017-01-01

Background Since mid-2013, Wisconsin abortion providers have been legally required to display and describe pre-abortion ultrasound images. We aimed to understand the impact of this law. Methods We used a mixed-methods study design at an abortion facility in Wisconsin. We abstracted data from medical charts one year before the law to one year after and used multivariable models, mediation/moderation analysis, and interrupted time series to assess the impact of the law, viewing, and decision certainty on likelihood of continuing the pregnancy. We conducted in-depth interviews with women in the post-law period about their ultrasound experience and analyzed them using elaborative and modified grounded theory. Results A total of 5342 charts were abstracted; 8.7% continued their pregnancies pre-law and 11.2% post-law (p = 0.002). A multivariable model confirmed the law was associated with higher odds of continuing pregnancy (aOR = 1.23, 95% CI: 1.01–1.50). Decision certainty (aOR = 6.39, 95% CI: 4.72–8.64) and having to pay fully out of pocket (aOR = 4.98, 95% CI: 3.86–6.41) were most strongly associated with continuing pregnancy. Ultrasound viewing fully mediated the relationship between the law and continuing pregnancy. Interrupted time series analyses found no significant effect of the law but may have been underpowered to detect such a small effect. Nineteen of twenty-three women interviewed viewed their ultrasound image. Most reported no impact on their abortion decision; five reported a temporary emotional impact or increased certainty about choosing abortion. Two women reported that viewing helped them decide to continue the pregnancy; both also described preexisting decision uncertainty. Conclusions This law caused an increase in viewing rates and a statistically significant but small increase in continuing pregnancy rates. However, the majority of women were certain of their abortion decision and the law did not change their decision. Other factors were more significant in women’s decision-making, suggesting evaluations of restrictive laws should take account of the broader social environment. PMID:28746377

Transition probabilities for general birth-death processes with applications in ecology, genetics, and evolution

PubMed Central

Crawford, Forrest W.; Suchard, Marc A.

2011-01-01

A birth-death process is a continuous-time Markov chain that counts the number of particles in a system over time. In the general process with n current particles, a new particle is born with instantaneous rate λn and a particle dies with instantaneous rate μn. Currently no robust and efficient method exists to evaluate the finite-time transition probabilities in a general birth-death process with arbitrary birth and death rates. In this paper, we first revisit the theory of continued fractions to obtain expressions for the Laplace transforms of these transition probabilities and make explicit an important derivation connecting transition probabilities and continued fractions. We then develop an efficient algorithm for computing these probabilities that analyzes the error associated with approximations in the method. We demonstrate that this error-controlled method agrees with known solutions and outperforms previous approaches to computing these probabilities. Finally, we apply our novel method to several important problems in ecology, evolution, and genetics. PMID:21984359

Effects of partial reinforcement and time between reinforced trials on terminal response rate in pigeon autoshaping.

PubMed

Gottlieb, Daniel A

2006-03-01

Partial reinforcement often leads to asymptotically higher rates of responding and number of trials with a response than does continuous reinforcement in pigeon autoshaping. However, comparisons typically involve a partial reinforcement schedule that differs from the continuous reinforcement schedule in both time between reinforced trials and probability of reinforcement. Two experiments examined the relative contributions of these two manipulations to asymptotic response rate. Results suggest that the greater responding previously seen with partial reinforcement is primarily due to differential probability of reinforcement and not differential time between reinforced trials. Further, once established, differences in responding are resistant to a change in stimulus and contingency. Secondary response theories of autoshaped responding (theories that posit additional response-augmenting or response-attenuating mechanisms specific to partial or continuous reinforcement) cannot fully accommodate the current body of data. It is suggested that researchers who study pigeon autoshaping train animals on a common task prior to training them under different conditions.

Optimization of lipase-catalyzed biodiesel by isopropanolysis in a continuous packed-bed reactor using response surface methodology.

PubMed

Chang, Cheng; Chen, Jiann-Hwa; Chang, Chieh-Ming J; Wu, Tsung-Ta; Shieh, Chwen-Jen

2009-10-31

Isopropanolysis reactions were performed using triglycerides with immobilized lipase in a solvent-free environment. This study modeled the degree of isopropanolysis of soybean oil in a continuous packed-bed reactor when Novozym 435 was used as the biocatalyst. Response surface methodology (RSM) and three-level-three-factor Box-Behnken design were employed to evaluate the effects of synthesis parameters, reaction temperature ( degrees C), flow rate (mL/min) and substrate molar ratio of isopropanol to soybean oil, on the percentage molar conversion of biodiesel by transesterification. The results show that flow rate and temperature have a significant effect on the percentage of molar conversion. On the basis of ridge max analysis, the optimum conditions for synthesis were as follows: flow rate 0.1 mL/min, temperature 51.5 degrees C and substrate molar ratio 1:4.14. The predicted value was 76.62+/-1.52% and actual experimental value was 75.62+/-0.81% molar conversion. Moreover, continuous enzymatic process for seven days did not show any appreciable decrease in the percent of molar conversion (75%). This work demonstrates the applicability of lipase catalysis to prepare isopropyl esters by transesterification in solvent-free system with a continuous packed-bed reactor for industrial production.

Perioperative Care and the Importance of Continuous Quality Improvement—A Controlled Intervention Study in Three Tanzanian Hospitals

PubMed Central

Mtatifikolo, Ferdinand; Ngoli, Baltazar; Neuner, Bruno; Wernecke, Klaus–Dieter; Spies, Claudia

2015-01-01

Introduction Surgical services are increasingly seen to reduce death and disability in Sub-Saharan Africa, where hospital-based mortality remains alarmingly high. This study explores two implementation approaches to improve the quality of perioperative care in a Tanzanian hospital. Effects were compared to a control group of two other hospitals in the region without intervention. Methods All hospitals conducted quality assessments with a Hospital Performance Assessment Tool. Changes in immediate outcome indicators after one and two years were compared to final outcome indicators such as Anaesthetic Complication Rate and Surgical Case Fatality Rate. Results Immediate outcome indicators for Preoperative Care in the intervention hospital improved (52.5% in 2009; 84.2% in 2011, p<0.001). Postoperative Inpatient Care initially improved to then decline again (63.3% in 2009; 70% in 2010; 58.6% in 2011). In the control group, preoperative care declined from 50.8% (2009) to 32.8% (2011, p <0.001), while postoperative care did not significantly change. Anaesthetic Complication Rate in the intervention hospital declined (1.89% before intervention; 0.96% after intervention, p = 0.006). Surgical Case Fatality Rate in the intervention hospital declined from 5.67% before intervention to 2.93% after intervention (p<0.0010). Surgical Case Fatality Rate in the control group was 4% before intervention and 3.8% after intervention (p = 0.411). Anaesthetic Complication Rate in the control group was not available. Discussion Immediate outcome indicators initially improved, while at the same time final outcome declined (Surgical Case Fatality, Anaesthetic Complication Rate). Compared to the control group, final outcome improved more in the intervention hospital, although the effect was not significant over the whole study period. Documentation of final outcome indicators seemed inconsistent. Immediate outcome indicators seem more helpful to steer the Continuous Quality Improvement program. Conclusion Specific interventions as part of Continuous Quality Improvement might lead to sustainable improvement of the quality of care, if embedded in a multi-faceted approach. PMID:26327392

Perioperative Care and the Importance of Continuous Quality Improvement--A Controlled Intervention Study in Three Tanzanian Hospitals.

PubMed

Bosse, Goetz; Abels, Wiltrud; Mtatifikolo, Ferdinand; Ngoli, Baltazar; Neuner, Bruno; Wernecke, Klaus-Dieter; Spies, Claudia

2015-01-01

Surgical services are increasingly seen to reduce death and disability in Sub-Saharan Africa, where hospital-based mortality remains alarmingly high. This study explores two implementation approaches to improve the quality of perioperative care in a Tanzanian hospital. Effects were compared to a control group of two other hospitals in the region without intervention. All hospitals conducted quality assessments with a Hospital Performance Assessment Tool. Changes in immediate outcome indicators after one and two years were compared to final outcome indicators such as Anaesthetic Complication Rate and Surgical Case Fatality Rate. Immediate outcome indicators for Preoperative Care in the intervention hospital improved (52.5% in 2009; 84.2% in 2011, p<0.001). Postoperative Inpatient Care initially improved to then decline again (63.3% in 2009; 70% in 2010; 58.6% in 2011). In the control group, preoperative care declined from 50.8% (2009) to 32.8% (2011, p <0.001), while postoperative care did not significantly change. Anaesthetic Complication Rate in the intervention hospital declined (1.89% before intervention; 0.96% after intervention, p = 0.006). Surgical Case Fatality Rate in the intervention hospital declined from 5.67% before intervention to 2.93% after intervention (p<0.0010). Surgical Case Fatality Rate in the control group was 4% before intervention and 3.8% after intervention (p = 0.411). Anaesthetic Complication Rate in the control group was not available. Immediate outcome indicators initially improved, while at the same time final outcome declined (Surgical Case Fatality, Anaesthetic Complication Rate). Compared to the control group, final outcome improved more in the intervention hospital, although the effect was not significant over the whole study period. Documentation of final outcome indicators seemed inconsistent. Immediate outcome indicators seem more helpful to steer the Continuous Quality Improvement program. Specific interventions as part of Continuous Quality Improvement might lead to sustainable improvement of the quality of care, if embedded in a multi-faceted approach.

Design of a lamella settler for biomass recycling in continuous ethanol fermentation process.

PubMed

Tabera, J; Iznaola, M A

1989-04-20

The design and application of a settler to a continuous fermentation process with yeast recycle were studied. The compact lamella-type settler was chosen to avoid large volumes associated with conventional settling tanks. A rationale of the design method is covered. The sedimentation area was determined by classical batch settling rate tests and sedimentation capacity calculation. Limitations on the residence time of the microorganisms in the settler, rather than sludge thickening considerations, was the approach employed for volume calculation. Fermentation rate tests with yeast after different sedimentation periods were carried out to define a suitable residence time. Continuous cell recycle fermentation runs, performed with the old and new sedimentation devices, show that lamella settler improves biomass recycling efficiency, being the process able to operate at higher sugar concentrations and faster dilution rates.

Physiological responses during continuous work in hot dry and hot humid environments in Indians

NASA Astrophysics Data System (ADS)

Sen Gupta, J.; Swamy, Y. V.; Pichan, G.; Dimri, G. P.

1984-06-01

Studies have been conducted on six young healthy heat acclimatised Indians to determine the physiological changes in prolonged continuous work in thermally neutral and in hot dry and hot humid environments. Physiological responses in maximal efforts i.e. Vo2 max, VE max and Cf max were noted. In addition, duration in continuous work at three sub-maximal rate of work in three simulated environments were also noted. Physiological responses like Vo2, VE and Cf were noted every 15 minutes of work. Besides these responses, rectal temperature (Tre), mean skin temperature (Ts) and mean sweat rate were also recorded during continuous work. Results indicated a significant decrease in maximum oxygen uptake capacity (Vo2 max) in heat with no change in maximum exercise ventilation (VE max) and maximum cardiac frequency. However, the fall in Vo2 max was more severe in the hot humid environment than in the hot dry climate. Cardiac frequency at fixed oxygen consumption of 1.0, 1.5 and 2.0 l/min was distinctly higher in the hot humid environment than in the hot dry and comfortable temperature. The duration in continuous physical effort in various grades of activities decreased in hot dry environment from that in the-comfortable climate and further decreased significantly in hot humid environment. The highest rate of sweating was observed during work in humid heat. The mean skin temperature (Ts) showed a fall in all the three rates of work in comfortable and hot dry conditions whereas in hot humid environment it showed a linear rise during the progress of work. The rectal temperature on the other hand maintained a near steady state while working at 65 and 82 watts in comfortable and hot dry environments but kept on rising during work in hot humid environment. At the highest work rate of 98 watts, the rectal temperature showed a steady increase even in the hot dry condition. It was thus concluded from the study that a hot humid climate imposes more constraints on the thermoregulatory system during work than in the hot dry condition because of less effective heat dissipation so resulting in reduced tolerance to work.

Delta progradation and Neoglaciation, Laguna Parón, Cordillera Blanca, Peru

NASA Astrophysics Data System (ADS)

Seltzer, Geoffrey O.; Rodbell, Donald T.

2005-10-01

The history of Holocene glaciation serves as an important record of glacier mass balance and, therefore, of climatic change. The moraine record of Holocene glaciation in the tropical Andes, however, is fragmentary and poorly dated. In contrast, increases in the rate of accumulation of inorganic sediment in glacier-fed lakes have been linked to periods of Neoglaciation in many mountain regions. The interpretation of such a record of Neoglaciation from sediment cores in glacier-fed lakes in the tropical Andes can provide the continuity and chronologic control that is lacking in the existing moraine record. Unusual exposures of glacial lacustrine sediment in the Cordillera Blanca, Peru, provide a rare opportunity to assess the link between climatic change, glaciation, and lacustrine sedimentation.Intentional lowering of water levels in Laguna Parón (9°S, 77°44 W, 4200 m a.s.l.) in 1985 resulted in the incision and exposure of at least 20 m of deltaic deposits at the eastern end of the lake. Three deltaic units can be identified: horizontal topset beds, steeply dipping and deformed foreset beds, and horizontally laminated fine-grained sediment. Six radiocarbon ages ranging from 1800 +/- 210 to 465 +/- 95 14C yr BP on wood indicate that the average rate of delta progradation in the late Holocene has been approximately 290 m per 1000 yr. The lake formed during deglaciation at least 10 000 yr ago and if such a rate of progradation of the delta had prevailed over the entire Holocene, then the delta would be at least three times as extensive as it is today. Thus the rate of delta progradation has varied significantly over the Holocene. We suggest that the rate of delta progradation was at least three times greater when glaciers were in advanced positions. These positions are clearly delimited by Neoglacial moraines, which are within 1-2 km of the exposures studied and within 1 km of modern ice limits. The most recent increase in the rate of delta progradation is evidenced by an increase in sedimentation rate ca. 575 +/- 90 14C yrBP, coincident with the onset of the Little Ice Age.

40 CFR 60.1820 - How do I monitor the injection rate of activated carbon?

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 7 2013-07-01 2013-07-01 false How do I monitor the injection rate of activated carbon? 60.1820 Section 60.1820 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) STANDARDS OF PERFORMANCE FOR NEW STATIONARY SOURCES Emission Guidelines and Compliance Times for Small Municipal...

40 CFR 60.1820 - How do I monitor the injection rate of activated carbon?

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 7 2014-07-01 2014-07-01 false How do I monitor the injection rate of activated carbon? 60.1820 Section 60.1820 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) STANDARDS OF PERFORMANCE FOR NEW STATIONARY SOURCES Emission Guidelines and Compliance Times for Small Municipal...

40 CFR 60.1820 - How do I monitor the injection rate of activated carbon?

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 7 2012-07-01 2012-07-01 false How do I monitor the injection rate of activated carbon? 60.1820 Section 60.1820 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) STANDARDS OF PERFORMANCE FOR NEW STATIONARY SOURCES Emission Guidelines and Compliance Times for Small Municipal...

40 CFR 60.1820 - How do I monitor the injection rate of activated carbon?

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 6 2011-07-01 2011-07-01 false How do I monitor the injection rate of activated carbon? 60.1820 Section 60.1820 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) STANDARDS OF PERFORMANCE FOR NEW STATIONARY SOURCES Emission Guidelines and Compliance Times for Small Municipal...

Frequency, trends, and antecedents of severe maternal depression after three million U.S. births.

PubMed

França, Urbano L; McManus, Michael L

2018-01-01

Postpartum depression carries adverse consequences for mothers and children, so widespread screening during primary care visits is recommended. However, the rates, timing, and factors associated with significant depressive episodes are incompletely understood. We examined the Healthcare Cost and Utilization Project (HCUP) State Inpatient, Emergency Department, and Ambulatory Surgery and Services Databases from California (2005-2011) and Florida (2005-2012). Within 203 million records, we identified 3,213,111 births and all mothers who had hospital encounters for severe depression within 40 weeks following delivery. We identified 15,806 episodes of postpartum depression after 11,103 deliveries among 10,883 unique women, and calculated an overall rate of 36.7 depression- associated hospital visits per 10,000 deliveries. Upward trends were observed in both states, with combined five-year increases of 34%. First depressive events were most common within 30 days of delivery, but continued for the entire observation period. About half (1,661/3,325) of PPD first episodes occurred within 34 days of delivery, 70% (2,329/3,325) by the end of the second month, and 87% (2,893/3,325) before four-months of the delivery. Women with private insurance were less likely to have hospital encounters for depression than women with public insurance and women with depression were much more likely to have had some kind of hospital encounter at some time during their pregnancies. Rates of depression increased with the number of prenatal hospital encounters in a "dose-dependent" fashion: the rate of depression was 17.2/10,000 for women with no prenatal hospital visits, doubling for women with at least one encounter (34.9/10,000), and increasing 7-fold to 126/10,000 for women with three or more encounters during their pregnancies. Our findings suggest that (1) hospital encounters for post-partum depression are increasing, (2) screening should begin very early and continue for the first year after delivery, and (3) added attention should be given to women who had hospital encounters during their pregnancies.

Effects of desensitizing toothpastes on the permeability of dentin after different brushing times: An in vitro study.

PubMed

Yang, Meng; Lin, Hong; Jiang, Ruodan; Zheng, Gang

2016-12-01

To investigate the effects of three commercially available desensitizing toothpastes on dentin permeability, and compare the efficacy of each product for reducing dentin permeability in the short term according to the frequency and duration of usage. 100 dentin discs with no caries were prepared from freshly extracted human third molar teeth. The dentin discs were brushed with three desensitizing toothpastes or with a non-desensitizing toothpaste and distilled water, which served as control. The 100 dentin slices were randomly divided into two groups (n= 50): one group underwent continuous brushing (brushed for 3 minutes continuously), and the other group underwent discontinuous brushing (brushed three times, each time for 1 minute). Then, the two groups were divided into five subgroups (n = 10) for the five brushing applications. Dentin permeability was measured with a hydraulic permeability system before and after brushing. All desensitizing toothpastes reduced dentin permeability significantly after treatment. Sensodyne Repair and Protect (calcium sodium phosphosilicate) and discontinuous brushing reduced dentin permeability significantly compared with continuous brushing. Dentin permeability values showed no significant difference between the three toothpastes after 3 minutes of continuous brushing. When comparing the three toothpastes under discontinuous brushing conditions after 3 minutes, Sensodyne Repair and Protect (calcium sodium phosphosilicate) reduced dentin permeability significantly. Sensodyne Repair and Protect (calcium sodium phosphosilicate) and discontinuous brushing reduced dentin permeability significantly compared with continuous brushing. Moreover, brushing with Sensodyne Repair and Protect (calcium sodium phosphosilicate) resulted in the lowest dentin permeability compared with those of the other two toothpastes. These results indicated that Sensodyne Repair and Protect may relieve dentin hypersensitivity.

The impact of continuous driving time and rest time on commercial drivers' driving performance and recovery.

PubMed

Wang, Lianzhen; Pei, Yulong

2014-09-01

This real road driving study was conducted to investigate the effects of driving time and rest time on the driving performance and recovery of commercial coach drivers. Thirty-three commercial coach drivers participated in the study, and were divided into three groups according to driving time: (a) 2 h, (b) 3 h, and (c) 4 h. The Stanford Sleepiness Scale (SSS) was used to assess the subjective fatigue level of the drivers. One-way ANOVA was employed to analyze the variation in driving performance. The statistical analysis revealed that driving time had a significant effect on the subjective fatigue and driving performance measures among the three groups. After 2 h of driving, both the subjective fatigue and driving performance measures began to deteriorate. After 4 h of driving, all of the driving performance indicators changed significantly except for depth perception. A certain amount of rest time eliminated the negative effects of fatigue. A 15-minute rest allowed drivers to recover from a two-hour driving task. This needed to be prolonged to 30 min for driving tasks of 3 to 4 h of continuous driving. Drivers' attention, reactions, operating ability, and perceptions are all affected in turn after over 2 h of continuous driving. Drivers should take a certain amount of rest to recover from the fatigue effects before they continue driving. Copyright © 2014 National Safety Council and Elsevier Ltd. All rights reserved.

[Sensitivity and specificity of the breast screening program in the Isere region based on positive results between 1991 and 1999].

PubMed

Garnier, A; Poncet, F; Billette De Villemeur, A; Exbrayat, C; Bon, M F; Chevalier, A; Salicru, B; Tournegros, J M

2009-06-01

The screening program guidelines specify that the call back rate of women for additional imaging (positive mammogram) should not exceed 7% at initial screening, and 5% at subsequent screening. Materials and methods. Results in the Isere region (12%) have prompted a review of the correlation between the call back rate and indicators of quality (detection rate, sensitivity, specificity, positive predictive value) for the radiologists providing interpretations during that time period. Three groups of radiologists were identified: the group with call back rate of 10% achieved the best results (sensitivity: 92%, detection rate: 0.53%, specificity: 90%). The group with lowest call back rate (7.7%) showed insufficient sensitivity (58%). The last group with call back rate of 18.3%, showed no improvement in sensitivity (82%) and detection rate (0.53%), but showed reduced specificity (82%). The protocol update in 2001 does not resolve this problematic situation and national results continue to demonstrate a high percentage of positive screening mammograms. A significant increase in the number of positive screening examinations compared to recommended guidelines is not advantageous and leads to an overall decrease in the quality of the screening.

The Stent Patency and Migration Rate of Different Shaped Plastic Stents in Bile Flow Phantom Model and In Vivo Animal Bile Duct Dilation Model.

PubMed

Kwon, Chang-Il; Kim, Gwangil; Jeong, Seok; Lee, Don Haeng; Kim, Kyoung Ah; Ko, Kwang Hyun; Cho, Joo Young; Hong, Sung Pyo

2017-05-01

In research and development of biliary plastic stents (PS), continuous efforts have been made to overcome short patency time and high rate of migration. The aim of this study was to evaluate the patency and migration rate of different PS shapes for a given period of time. Using an in vitro bile phantom model, we compared the patency among different shapes of PS (three straight PS, four double-pigtail PS, and a new screw-shaped PS). We performed an analysis of the degree of luminal narrowing by light microscopic examination. Using an in vivo swine model, we compared the patency and migration rate among the three different types of PS. Eight weeks after the bile exposure in the bile flow phantom model, 80 PS were retrieved and analyzed. The straight PS showed less biofilm formation and luminal narrowing than other types of PS (p < 0.05). Forty-nine PS were inserted into the dilated bile ducts of 10 swine models, and 39 PS were successfully retrieved 8 weeks later. The stent migration occurred less frequently in the double-pigtail PS and the screw-shaped PS than it did in the straight PS (11.1, 10, and 27.3%, respectively). However, there was no statistical difference in stent patency among the different shapes. Stent patency may not be significantly different depending on the shape of PS for 8 weeks. The screw-shaped PS showed similar patency and migration rate to the double-pigtail PS. These results may help guiding future PS development and clinical decisions.

Time-averaged exposures to 220Rn and 222Rn progeny in Colorado homes.

PubMed

Martz, D E; Falco, R J; Langner, G H

1990-06-01

Week-long time-averaged exposures to naturally occurring 220Rn and 222Rn progeny have been measured at several locations in Colorado by monitoring the alpha activity collected continuously on a fixed-membrane filter. The alpha-energy spectrum associated with the activity collected on the filter was recorded every 15 min using a microcomputer-controlled alpha spectrometer. The alpha counts observed in three energy regions permitted complete separation of the contributions from each decay chain, and calculation of the separate time-averaged potential alpha-energy concentrations in air from 220Rn progeny, PAEC(Tn), and from 222Rn progeny, PAEC(Rn). The time-averaged PAEC(Tn) ranged from 0.3 to 6.9 mWL at 12 indoor locations, and the time-averaged PAEC(Rn) ranged from 1.0 to 59.0 mWL. The ratios of the indoor PAEC(Tn) to indoor PAEC(Rn) ranged from 0.09 to 0.58, with an overall average ratio of 0.32 and a standard deviation of 0.15. The 10 L min-1 flow rate through the filter was selected to approximate the air intake rate of a resting human; the time-averaged PAEC thus represents the progeny concentrations that would have been inhaled by a person breathing the same atmosphere.

Real time three-dimensional space video rate sensors for millimeter waves imaging based very inexpensive plasma LED lamps

NASA Astrophysics Data System (ADS)

Levanon, Assaf; Yitzhaky, Yitzhak; Kopeika, Natan S.; Rozban, Daniel; Abramovich, Amir

2014-10-01

In recent years, much effort has been invested to develop inexpensive but sensitive Millimeter Wave (MMW) detectors that can be used in focal plane arrays (FPAs), in order to implement real time MMW imaging. Real time MMW imaging systems are required for many varied applications in many fields as homeland security, medicine, communications, military products and space technology. It is mainly because this radiation has high penetration and good navigability through dust storm, fog, heavy rain, dielectric materials, biological tissue, and diverse materials. Moreover, the atmospheric attenuation in this range of the spectrum is relatively low and the scattering is also low compared to NIR and VIS. The lack of inexpensive room temperature imaging systems makes it difficult to provide a suitable MMW system for many of the above applications. In last few years we advanced in research and development of sensors using very inexpensive (30-50 cents) Glow Discharge Detector (GDD) plasma indicator lamps as MMW detectors. This paper presents three kinds of GDD sensor based lamp Focal Plane Arrays (FPA). Those three kinds of cameras are different in the number of detectors, scanning operation, and detection method. The 1st and 2nd generations are 8 × 8 pixel array and an 18 × 2 mono-rail scanner array respectively, both of them for direct detection and limited to fixed imaging. The last designed sensor is a multiplexing frame rate of 16x16 GDD FPA. It permits real time video rate imaging of 30 frames/ sec and comprehensive 3D MMW imaging. The principle of detection in this sensor is a frequency modulated continuous wave (FMCW) system while each of the 16 GDD pixel lines is sampled simultaneously. Direct detection is also possible and can be done with a friendly user interface. This FPA sensor is built over 256 commercial GDD lamps with 3 mm diameter International Light, Inc., Peabody, MA model 527 Ne indicator lamps as pixel detectors. All three sensors are fully supported by software Graphical Unit Interface (GUI). They were tested and characterized through different kinds of optical systems for imaging applications, super resolution, and calibration methods. Capability of the 16x16 sensor is to employ a chirp radar like method to produced depth and reflectance information in the image. This enables 3-D MMW imaging in real time with video frame rate. In this work we demonstrate different kinds of optical imaging systems. Those systems have capability of 3-D imaging for short range and longer distances to at least 10-20 meters.

IMPAC: An Integrated Methodology for Propulsion and Airframe Control

NASA Technical Reports Server (NTRS)

Garg, Sanjay; Ouzts, Peter J.; Lorenzo, Carl F.; Mattern, Duane L.

1991-01-01

The National Aeronautics and Space Administration is actively involved in the development of enabling technologies that will lead towards aircraft with new/enhanced maneuver capabilities such as Short Take-Off Vertical Landing (STOVL) and high angle of attack performance. Because of the high degree of dynamic coupling between the airframe and propulsion systems of these types of aircraft, one key technology is the integration of the flight and propulsion control. The NASA Lewis Research Center approach to developing Integrated Flight Propulsion Control (IFPC) technologies is an in-house research program referred to as IMPAC (Integrated Methodology for Propulsion and Airframe Control). The goals of IMPAC are to develop a viable alternative to the existing integrated control design methodologies that will allow for improved system performance and simplicity of control law synthesis and implementation, and to demonstrate the applicability of the methodology to a supersonic STOVL fighter aircraft. Based on some preliminary control design studies that included evaluation of the existing methodologies, the IFPC design methodology that is emerging at the Lewis Research Center consists of considering the airframe and propulsion system as one integrated system for an initial centralized controller design and then partitioning the centralized controller into separate airframe and propulsion system subcontrollers to ease implementation and to set meaningful design requirements for detailed subsystem control design and evaluation. An overview of IMPAC is provided and detailed discussion of the various important design and evaluation steps in the methodology are included.

Peripheral Vasculature: High-Temporal- and High-Spatial-Resolution Three-dimensional Contrast-enhanced MR Angiography1

PubMed Central

Haider, Clifton R.; Glockner, James F.; Stanson, Anthony W.; Riederer, Stephen J.

2009-01-01

Purpose: To prospectively evaluate the feasibility of performing high-spatial-resolution (1-mm isotropic) time-resolved three-dimensional (3D) contrast material–enhanced magnetic resonance (MR) angiography of the peripheral vasculature with Cartesian acquisition with projection-reconstruction–like sampling (CAPR) and eightfold accelerated two-dimensional (2D) sensitivity encoding (SENSE). Materials and Methods: All studies were approved by the institutional review board and were HIPAA compliant; written informed consent was obtained from all participants. There were 13 volunteers (mean age, 41.9; range, 27–53 years). The CAPR sequence was adapted to provide 1-mm isotropic spatial resolution and a 5-second frame time. Use of different receiver coil element sizes for those placed on the anterior-to-posterior versus left-to-right sides of the field of view reduced signal-to-noise ratio loss due to acceleration. Results from eight volunteers were rated independently by two radiologists according to prominence of artifact, arterial to venous separation, vessel sharpness, continuity of arterial signal intensity in major arteries (anterior and posterior tibial, peroneal), demarcation of origin of major arteries, and overall diagnostic image quality. MR angiographic results in two patients with peripheral vascular disease were compared with their results at computed tomographic angiography. Results: The sequence exhibited no image artifact adversely affecting diagnostic image quality. Temporal resolution was evaluated to be sufficient in all cases, even with known rapid arterial to venous transit. The vessels were graded to have excellent sharpness, continuity, and demarcation of the origins of the major arteries. Distal muscular branches and the communicating and perforating arteries were routinely seen. Excellent diagnostic quality rating was given for 15 (94%) of 16 evaluations. Conclusion: The feasibility of performing high-diagnostic-quality time-resolved 3D contrast-enhanced MR angiography of the peripheral vasculature by using CAPR and eightfold accelerated 2D SENSE has been demonstrated. © RSNA, 2009 Supplemental material: http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.2533081744/-/DC1 PMID:19789238

Dealing with Time in Health Economic Evaluation: Methodological Issues and Recommendations for Practice.

PubMed

O'Mahony, James F; Newall, Anthony T; van Rosmalen, Joost

2015-12-01

Time is an important aspect of health economic evaluation, as the timing and duration of clinical events, healthcare interventions and their consequences all affect estimated costs and effects. These issues should be reflected in the design of health economic models. This article considers three important aspects of time in modelling: (1) which cohorts to simulate and how far into the future to extend the analysis; (2) the simulation of time, including the difference between discrete-time and continuous-time models, cycle lengths, and converting rates and probabilities; and (3) discounting future costs and effects to their present values. We provide a methodological overview of these issues and make recommendations to help inform both the conduct of cost-effectiveness analyses and the interpretation of their results. For choosing which cohorts to simulate and how many, we suggest analysts carefully assess potential reasons for variation in cost effectiveness between cohorts and the feasibility of subgroup-specific recommendations. For the simulation of time, we recommend using short cycles or continuous-time models to avoid biases and the need for half-cycle corrections, and provide advice on the correct conversion of transition probabilities in state transition models. Finally, for discounting, analysts should not only follow current guidance and report how discounting was conducted, especially in the case of differential discounting, but also seek to develop an understanding of its rationale. Our overall recommendations are that analysts explicitly state and justify their modelling choices regarding time and consider how alternative choices may impact on results.

Wireless non-invasive continuous respiratory monitoring with FMCW radar: a clinical validation study.

PubMed

van Loon, K; Breteler, M J M; van Wolfwinkel, L; Rheineck Leyssius, A T; Kossen, S; Kalkman, C J; van Zaane, B; Peelen, L M

2016-12-01

Altered respiratory rate is one of the first symptoms of medical conditions that require timely intervention, e.g., sepsis or opioid-induced respiratory depression. To facilitate continuous respiratory rate monitoring on general hospital wards a contactless, non-invasive, prototype monitor was developed using frequency modulated continuous wave radar. We aimed to study whether radar can reliably measure respiratory rate in postoperative patients. In a diagnostic cross-sectional study patients were monitored with the radar and the reference monitor (pneumotachograph during mechanical ventilation and capnography during spontaneous breathing). Eight patients were included; yielding 796 min of observation time during mechanical ventilation and 521 min during spontaneous breathing. After elimination of movement artifacts the bias and 95 % limits of agreement for mechanical ventilation and spontaneous breathing were -0.12 (-1.76 to 1.51) and -0.59 (-5.82 to 4.63) breaths per minute respectively. The radar was able to accurately measure respiratory rate in mechanically ventilated patients, but the accuracy decreased during spontaneous breathing.

Commercialization Issues For Catheter-Based Electrochemical Sensors

NASA Astrophysics Data System (ADS)

Nikolchev, Julian; Gaisford, Scott

1989-08-01

The need for continuous monitoring of key clinical parameters in hospitals is well recognized. Figure 1 shows typical time constants for blood gases, ions and enzymes in response to acute ventilatory changes and interventions. Although it can be seen that relatively low rates of data collection are necessary for many medical measurements, it is also clear that intermittent measurement of P02, PCO2 and pH are not sufficient to provide safe and effective management of the patient. Very frequent or continuous monitoring is often essential. This figure also shows why the emphasis of a large number of research efforts in this country and in Europe and Japan have as their goal the development of continuous blood gas sensors, i.e., sensors that continuously monitor blood pH, partial pressure of oxygen and partial pressure of carbon dioxide. These are three (3) of the most frequent parameters measured in hospitals and the ones having the shortest time constant. Considering that in the United States alone close to 25 million blood gas samples per year are taken from patients, the potential market for continuous monitoring sensors is enormous. The emergence of microelectronics and microfabrication technologies over the past 30 years are now pointing to a possible resolution of the well recognized need for real time monitoring of critically ill patients through catheter-based sensors. Although physicians will always prefer non-invasive monitoring techniques, there are a number of parameters that presently can only be monitored by invasive method. The emerging ability to miniaturize chemical sensors using silicon microfabrication or fiber-optic techniques offer an excellent opportunity to solve this need. In fact, the development of in vivo biomedical sensors with satisfactory performance characteristics has long been considered the ultimate application of these emerging technologies.

Queue position in the endoscopic schedule impacts effectiveness of colonoscopy.

PubMed

Lee, Alexander; Iskander, John M; Gupta, Nitin; Borg, Brian B; Zuckerman, Gary; Banerjee, Bhaskar; Gyawali, C Prakash

2011-08-01

Endoscopist fatigue potentially impacts colonoscopy. Fatigue is difficult to quantitate, but polyp detection rates between non-fatigued and fatigued time periods could represent a surrogate marker. We assessed whether timing variables impacted polyp detection rates at a busy tertiary care endoscopy suite. Consecutive patients undergoing colonoscopy were retrospectively identified. Indications, clinical demographics, pre-procedural, and procedural variables were extracted from chart review; colonoscopy findings were determined from the procedure reports. Three separate timing variables were assessed as surrogate markers for endoscopist fatigue: morning vs. afternoon procedures, start times throughout the day, and queue position, a unique variable that takes into account the number of procedures performed before the colonoscopy of interest. Univariate and multivariate analyses were performed to determine whether timing variables and other clinical, pre-procedural, and procedural variables predicted polyp detection. During the 4-month study period, 1,083 outpatient colonoscopy procedures (57.5±0.5 years, 59.5% female) were identified, performed by 28 endoscopists (mean 38.7 procedures/endoscopist), with a mean polyp detection rate of 0.851/colonoscopy. At least, one adenoma was detected in 297 procedures (27.4%). A 12.4% reduction in mean detected polyps was detected between morning and afternoon procedures (0.90±0.06 vs. 0.76±0.06, P=0.15). Using start time on a continuous scale, however, each elapsed hour in the day was associated with a 4.6% reduction in polyp detection (P=0.005). When queue position was assessed, a 5.4% reduction in polyp detection was noted with each increase in queue position (P=0.016). These results remained significant when controlled for each individual endoscopist. Polyp detection rates decline as time passes during an endoscopist's schedule, potentially from endoscopist fatigue. Queue position may be a novel surrogate measure for operator fatigue.

On the continuous dependence with respect to sampling of the linear quadratic regulator problem for distributed parameter systems

NASA Technical Reports Server (NTRS)

Rosen, I. G.; Wang, C.

1990-01-01

The convergence of solutions to the discrete or sampled time linear quadratic regulator problem and associated Riccati equation for infinite dimensional systems to the solutions to the corresponding continuous time problem and equation, as the length of the sampling interval (the sampling rate) tends toward zero (infinity) is established. Both the finite and infinite time horizon problems are studied. In the finite time horizon case, strong continuity of the operators which define the control system and performance index together with a stability and consistency condition on the sampling scheme are required. For the infinite time horizon problem, in addition, the sampled systems must be stabilizable and detectable, uniformly with respect to the sampling rate. Classes of systems for which this condition can be verified are discussed. Results of numerical studies involving the control of a heat/diffusion equation, a hereditary of delay system, and a flexible beam are presented and discussed.

On the continuous dependence with respect to sampling of the linear quadratic regulator problem for distributed parameter system

NASA Technical Reports Server (NTRS)

Rosen, I. G.; Wang, C.

1992-01-01

The convergence of solutions to the discrete- or sampled-time linear quadratic regulator problem and associated Riccati equation for infinite-dimensional systems to the solutions to the corresponding continuous time problem and equation, as the length of the sampling interval (the sampling rate) tends toward zero(infinity) is established. Both the finite-and infinite-time horizon problems are studied. In the finite-time horizon case, strong continuity of the operators that define the control system and performance index, together with a stability and consistency condition on the sampling scheme are required. For the infinite-time horizon problem, in addition, the sampled systems must be stabilizable and detectable, uniformly with respect to the sampling rate. Classes of systems for which this condition can be verified are discussed. Results of numerical studies involving the control of a heat/diffusion equation, a hereditary or delay system, and a flexible beam are presented and discussed.

Histories of poverty and self-rated health trajectories.

PubMed

McDonough, Peggy; Berglund, Pat

2003-06-01

This paper investigates the dynamic relationship between poverty histories and self-rated health trajectories. We are interested in patterns of change in individuals' health over time and the ways in which such patterns are structured by continuity and change in poverty experiences. Data, collected for adults aged 25 and older in 1984 (N = 7,258), are from the 1968-1996 annual waves of Panel Study of Income Dynamics (PSID). Individual growth curves allow us to investigate health trajectories as continuous processes, as well as individual and group heterogeneity in these trajectories. We find that, on average, health deteriorates slowly over time, but there is significant variation in health in 1984 and the rate at which health declines. Histories of poverty partly accounted for the sources of individual differences in self-rated health in 1984, but they were not related to health change over time. Although increasing incomes were better for self-rated health than falling incomes, current economic circumstances did not erase the health effects of earlier poverty experiences.

AiRCare: A naturalistic evaluation of the effectiveness of a protracted telephone-based recovery assistance program on continuing care outcomes.

PubMed

Proctor, Steven L; Wainwright, Jaclyn L; Herschman, Philip L; Kopak, Albert M

2017-02-01

Substance use disorder treatments are increasingly being contextualized within a disease management framework. Within this context, there is an identified need to maintain patients in treatment for longer periods of time in order to help them learn how to manage their disease. One way to meet this need is through telephone-based interventions that engage patients, and include more active outreach attempts and involvement of the patient's family. This study sought to evaluate the effectiveness of three formats of an intensive 12-month post-discharge telephone-based case management approach (AiRCare) on adherence to continuing care plans and substance use outcomes. Data were abstracted from electronic medical records for 379 patients (59.9% male) discharged from a residential treatment program located in the southwestern U.S. from 2013 to 2015. Patients were categorized into one of three groups and received telephone contacts based on their self-selection upon admission to residential treatment (i.e., patient only, family only, and both patient and family). Outcome variables included re-engagement and re-admission rates, quality of life, abstinence rates at 6 and 12 months, and compliance with continuing care plans. Favorable short- and long-term outcomes were found for the majority of patients, irrespective of case management group. There appeared to be some value in the addition of family contacts to patient contacts with respect to reducing risk for 12-month re-admission to residential care. These positive but preliminary indications of the effectiveness of AiRCare require replication in a well-powered, randomized controlled trial. Copyright © 2016 Elsevier Inc. All rights reserved.

Characterization of the surfaces of platinum/tin oxide based catalysts by Fourier transform spectroscopy (FTIR)

NASA Technical Reports Server (NTRS)

Keiser, Joseph T.

1989-01-01

The Laser Atmospheric Wind Sounder (LAWS) Program has as one of its goals the development of a satellite based carbon dioxide laser for making wind velocity measurements. The specifications for this laser include the requirement that the laser operate at a repetition rate of 10 Hertz continuously for three years. Earth-based carbon dioxide lasers can operate for only a short time on a single charge of gas because the lasing action causes the CO2 to break down into CO and O2. Therefore, earth-based CO2 lasers are generally operated in a flow through mode in which the spent gas is continually exhausted and fresh gas is continually added. For a satellite based system, however, a recirculation system is desired because it is not practical to send up extra tanks of CO2. A catalyst which could enable a recirculating CO2 laser to function continuously for three years needs to be developed. In the development of a catalyst system there are many variables. Obviously, not all possible formulations can be tested for three years, therefore, an accurate model which is based on the reaction mechanism is needed. The construction of a multistep reaction mechanism is similar to the construction of a jigsaw puzzle. Different techniques each supply a piece of the puzzle and the researcher must put the pieces together. Transmission infrared spectroscopy was shown to be very useful in supplying some of the information needed to elucidate reaction mechanisms. The purpose was to see what kind of information might be obtained about the NASA catalyst using infrared absorption spectroscopy. Approximately 200 infrared spectra of the prototype Pt/tin oxide catalyst and its precursor components are observed under a variety of different conditions. The most significant observations are summarized.

Generalization bounds of ERM-based learning processes for continuous-time Markov chains.

PubMed

Zhang, Chao; Tao, Dacheng

2012-12-01

Many existing results on statistical learning theory are based on the assumption that samples are independently and identically distributed (i.i.d.). However, the assumption of i.i.d. samples is not suitable for practical application to problems in which samples are time dependent. In this paper, we are mainly concerned with the empirical risk minimization (ERM) based learning process for time-dependent samples drawn from a continuous-time Markov chain. This learning process covers many kinds of practical applications, e.g., the prediction for a time series and the estimation of channel state information. Thus, it is significant to study its theoretical properties including the generalization bound, the asymptotic convergence, and the rate of convergence. It is noteworthy that, since samples are time dependent in this learning process, the concerns of this paper cannot (at least straightforwardly) be addressed by existing methods developed under the sample i.i.d. assumption. We first develop a deviation inequality for a sequence of time-dependent samples drawn from a continuous-time Markov chain and present a symmetrization inequality for such a sequence. By using the resultant deviation inequality and symmetrization inequality, we then obtain the generalization bounds of the ERM-based learning process for time-dependent samples drawn from a continuous-time Markov chain. Finally, based on the resultant generalization bounds, we analyze the asymptotic convergence and the rate of convergence of the learning process.

Continuous- and discrete-time stimulus sequences for high stimulus rate paradigm in evoked potential studies.

PubMed

Wang, Tao; Huang, Jiang-hua; Lin, Lin; Zhan, Chang'an A

2013-01-01

To obtain reliable transient auditory evoked potentials (AEPs) from EEGs recorded using high stimulus rate (HSR) paradigm, it is critical to design the stimulus sequences of appropriate frequency properties. Traditionally, the individual stimulus events in a stimulus sequence occur only at discrete time points dependent on the sampling frequency of the recording system and the duration of stimulus sequence. This dependency likely causes the implementation of suboptimal stimulus sequences, sacrificing the reliability of resulting AEPs. In this paper, we explicate the use of continuous-time stimulus sequence for HSR paradigm, which is independent of the discrete electroencephalogram (EEG) recording system. We employ simulation studies to examine the applicability of the continuous-time stimulus sequences and the impacts of sampling frequency on AEPs in traditional studies using discrete-time design. Results from these studies show that the continuous-time sequences can offer better frequency properties and improve the reliability of recovered AEPs. Furthermore, we find that the errors in the recovered AEPs depend critically on the sampling frequencies of experimental systems, and their relationship can be fitted using a reciprocal function. As such, our study contributes to the literature by demonstrating the applicability and advantages of continuous-time stimulus sequences for HSR paradigm and by revealing the relationship between the reliability of AEPs and sampling frequencies of the experimental systems when discrete-time stimulus sequences are used in traditional manner for the HSR paradigm.

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

Rehman, Nasir, E-mail: nasirzainy1@hotmail.com; Shashiashvili, Malkhaz

The classical Garman-Kohlhagen model for the currency exchange assumes that the domestic and foreign currency risk-free interest rates are constant and the exchange rate follows a log-normal diffusion process.In this paper we consider the general case, when exchange rate evolves according to arbitrary one-dimensional diffusion process with local volatility that is the function of time and the current exchange rate and where the domestic and foreign currency risk-free interest rates may be arbitrary continuous functions of time. First non-trivial problem we encounter in time-dependent case is the continuity in time argument of the value function of the American put optionmore » and the regularity properties of the optimal exercise boundary. We establish these properties based on systematic use of the monotonicity in volatility for the value functions of the American as well as European options with convex payoffs together with the Dynamic Programming Principle and we obtain certain type of comparison result for the value functions and corresponding exercise boundaries for the American puts with different strikes, maturities and volatilities.Starting from the latter fact that the optimal exercise boundary curve is left continuous with right-hand limits we give a mathematically rigorous and transparent derivation of the significant early exercise premium representation for the value function of the American foreign exchange put option as the sum of the European put option value function and the early exercise premium.The proof essentially relies on the particular property of the stochastic integral with respect to arbitrary continuous semimartingale over the predictable subsets of its zeros. We derive from the latter the nonlinear integral equation for the optimal exercise boundary which can be studied by numerical methods.« less

Approaching near real-time biosensing: microfluidic microsphere based biosensor for real-time analyte detection.

PubMed

Cohen, Noa; Sabhachandani, Pooja; Golberg, Alexander; Konry, Tania

2015-04-15

In this study we describe a simple lab-on-a-chip (LOC) biosensor approach utilizing well mixed microfluidic device and a microsphere-based assay capable of performing near real-time diagnostics of clinically relevant analytes such cytokines and antibodies. We were able to overcome the adsorption kinetics reaction rate-limiting mechanism, which is diffusion-controlled in standard immunoassays, by introducing the microsphere-based assay into well-mixed yet simple microfluidic device with turbulent flow profiles in the reaction regions. The integrated microsphere-based LOC device performs dynamic detection of the analyte in minimal amount of biological specimen by continuously sampling micro-liter volumes of sample per minute to detect dynamic changes in target analyte concentration. Furthermore we developed a mathematical model for the well-mixed reaction to describe the near real time detection mechanism observed in the developed LOC method. To demonstrate the specificity and sensitivity of the developed real time monitoring LOC approach, we applied the device for clinically relevant analytes: Tumor Necrosis Factor (TNF)-α cytokine and its clinically used inhibitor, anti-TNF-α antibody. Based on the reported results herein, the developed LOC device provides continuous sensitive and specific near real-time monitoring method for analytes such as cytokines and antibodies, reduces reagent volumes by nearly three orders of magnitude as well as eliminates the washing steps required by standard immunoassays. Copyright © 2014 Elsevier B.V. All rights reserved.

Time series models on analysing mortality rates and acute childhood lymphoid leukaemia.

PubMed

Kis, Maria

2005-01-01

In this paper we demonstrate applying time series models on medical research. The Hungarian mortality rates were analysed by autoregressive integrated moving average models and seasonal time series models examined the data of acute childhood lymphoid leukaemia.The mortality data may be analysed by time series methods such as autoregressive integrated moving average (ARIMA) modelling. This method is demonstrated by two examples: analysis of the mortality rates of ischemic heart diseases and analysis of the mortality rates of cancer of digestive system. Mathematical expressions are given for the results of analysis. The relationships between time series of mortality rates were studied with ARIMA models. Calculations of confidence intervals for autoregressive parameters by tree methods: standard normal distribution as estimation and estimation of the White's theory and the continuous time case estimation. Analysing the confidence intervals of the first order autoregressive parameters we may conclude that the confidence intervals were much smaller than other estimations by applying the continuous time estimation model.We present a new approach to analysing the occurrence of acute childhood lymphoid leukaemia. We decompose time series into components. The periodicity of acute childhood lymphoid leukaemia in Hungary was examined using seasonal decomposition time series method. The cyclic trend of the dates of diagnosis revealed that a higher percent of the peaks fell within the winter months than in the other seasons. This proves the seasonal occurrence of the childhood leukaemia in Hungary.

Examining solutions to missing data in longitudinal nursing research.

PubMed

Roberts, Mary B; Sullivan, Mary C; Winchester, Suzy B

2017-04-01

Longitudinal studies are highly valuable in pediatrics because they provide useful data about developmental patterns of child health and behavior over time. When data are missing, the value of the research is impacted. The study's purpose was to (1) introduce a three-step approach to assess and address missing data and (2) illustrate this approach using categorical and continuous-level variables from a longitudinal study of premature infants. A three-step approach with simulations was followed to assess the amount and pattern of missing data and to determine the most appropriate imputation method for the missing data. Patterns of missingness were Missing Completely at Random, Missing at Random, and Not Missing at Random. Missing continuous-level data were imputed using mean replacement, stochastic regression, multiple imputation, and fully conditional specification (FCS). Missing categorical-level data were imputed using last value carried forward, hot-decking, stochastic regression, and FCS. Simulations were used to evaluate these imputation methods under different patterns of missingness at different levels of missing data. The rate of missingness was 16-23% for continuous variables and 1-28% for categorical variables. FCS imputation provided the least difference in mean and standard deviation estimates for continuous measures. FCS imputation was acceptable for categorical measures. Results obtained through simulation reinforced and confirmed these findings. Significant investments are made in the collection of longitudinal data. The prudent handling of missing data can protect these investments and potentially improve the scientific information contained in pediatric longitudinal studies. © 2017 Wiley Periodicals, Inc.

The effects on human sleep and circadian rhythms of 17 days of continuous bedrest in the absence of daylight

NASA Technical Reports Server (NTRS)

Monk, T. H.; Buysse, D. J.; Billy, B. D.; Kennedy, K. S.; Kupfer, D. J.

1997-01-01

As part of a larger bedrest study involving various life science experiments, a study was conducted on the effects of 17 days of continuous bedrest and elimination of daylight on circadian rectal temperature rhythms, mood, alertness, and sleep (objective and diary) in eight healthy middle-aged men. Sleep was timed from 2300 to 0700 hours throughout. Three 72-hour measurement blocks were compared: ambulatory prebedrest, early bedrest (days 5-7), and late bedrest (days 15-17). Temperature rhythms showed reduced amplitude and later phases resulting from the bedrest conditions. This was associated with longer nocturnal sleep onset latencies and poorer subjectively rated sleep but with no reliable changes in any of the other sleep parameters. Daily changes in posture and/or exposure to daylight appear to be important determinants of a properly entrained circadian system.

Real-time imaging through strongly scattering media: seeing through turbid media, instantly

PubMed Central

Sudarsanam, Sriram; Mathew, James; Panigrahi, Swapnesh; Fade, Julien; Alouini, Mehdi; Ramachandran, Hema

2016-01-01

Numerous everyday situations like navigation, medical imaging and rescue operations require viewing through optically inhomogeneous media. This is a challenging task as photons propagate predominantly diffusively (rather than ballistically) due to random multiple scattering off the inhomogenieties. Real-time imaging with ballistic light under continuous-wave illumination is even more challenging due to the extremely weak signal, necessitating voluminous data-processing. Here we report imaging through strongly scattering media in real-time and at rates several times the critical flicker frequency of the eye, so that motion is perceived as continuous. Two factors contributed to the speedup of more than three orders of magnitude over conventional techniques - the use of a simplified algorithm enabling processing of data on the fly, and the utilisation of task and data parallelization capabilities of typical desktop computers. The extreme simplicity of the technique, and its implementation with present day low-cost technology promises its utility in a variety of devices in maritime, aerospace, rail and road transport, in medical imaging and defence. It is of equal interest to the common man and adventure sportsperson like hikers, divers, mountaineers, who frequently encounter situations requiring realtime imaging through obscuring media. As a specific example, navigation under poor visibility is examined. PMID:27114106

EXPLORING THE TIME DISPERSION OF THE IBEX-HI ENERGETIC NEUTRAL ATOM SPECTRA AT THE ECLIPTIC POLES

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

Allegrini, F.; Dayeh, M. A.; Desai, M. I.

2012-04-20

The Interstellar Boundary Explorer (IBEX) has observed energetic neutral atom (ENA) hydrogen emissions from the edge of the solar system for more than three years. The observations span energies from 0.01 to 6 keV FWHM. At energies greater than 0.5-6 keV, and for a travel distance of {approx}100 AU, the travel time difference between the slowest and the fastest ENA is more than a year. Therefore, we construct spectra including the effect that slower ENAs left the source at an earlier time than faster ones. If the source produces a steady rate of ENAs and the extinction does not vary,more » then we expect that the spectral shape would be time independent. However, while the extinction of ENAs has been fairly constant during the first two and a half years, the source appears to have changed, and thus the spectra at a single time may not represent the conditions at the source. IBEX's viewing allows continuous sampling of the ecliptic poles where fluxes can be continuously monitored. For a given source distance we construct spectra assuming that the measured ENAs left the source at roughly the same time. To accomplish this construction, we apply time lag corrections to the signal at different ENA energies that take into account the travel time difference. We show that the spectral shape at the poles exhibits a statistically significant change with time.« less

Compact single mode tunable laser using a digital micromirror device.

PubMed

Havermeyer, Frank; Ho, Lawrence; Moser, Christophe

2011-07-18

The wavelength tuning properties of a tunable external cavity laser based on multiplexed volume holographic gratings and a commercial micromirror device are reported. The 3x3x3 cm(3) laser exhibits single mode operation in single or multi colors between 776 nm and 783 nm with less than 7.5 MHz linewidth, 37 mW output power, 50 μs rise/fall time constant and a maximum switching rate of 0.66 KHz per wavelength. The unique discrete-wavelength-switching features of this laser are also well suited as a source for continuous wave Terahertz generation and three-dimensional metrology.

Long term attenuation statistics at 11.6 GHz in the three Italian Main Stations

NASA Astrophysics Data System (ADS)

Carassa, Francesco; Mauri, Mario; Paraboni, Aldo

1987-04-01

Results are presented from the 5-year attenuation-measurement campaign conducted with the SIRIO satellite at 11.6 and 17.8, which used near-continuous measurements at the lower frequency from the Italian ground stations at Fucino, Lario, and Spino d'Adda, and fewer measurements at the higher frequency from Fucino and Lario. The long-term statistics thus obtained have been applied in the design of the Italian domestic satellite system Italsat, which is to begin operating in 1989. Attention is presently given to annual worst month, time-of-day dependence, rain rate attenuation correlation, and frequency scaling statistics.

The big ban on bituminous coal sales revisited: Serious epidemics and pronounced trends feign excess mortality previously attributed to heavy black-smoke exposure

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

Wittmaack, K.

The effect of banning bituminous coal sales on the black-smoke concentration and the mortality rates in Dublin, Ireland, has been analyzed recently. Based on the application of standard epidemiological procedures, the authors concluded that, as a result of the ban, the total nontrauma death rate was reduced strongly (-8.0% unadjusted, -5.7% adjusted). The purpose of this study was to reanalyze the original data with the aim of clarifying the three most important aspects of the study, (a) the effect of epidemics, (b) the trends in mortality rates due to advances in public health care, and (c) the correlation between mortalitymore » rates and black-smoke concentrations. Particular attention has been devoted to a detailed evaluation of the time dependence of mortality rates, stratified by season. Death rates were found to be strongly enhanced during three severe pre-ban winter-spring epidemics. The cardiovascular mortality rates exhibited a continuous decrease over the whole study period, in general accordance with trends in the rest of Ireland. These two effects can fully account for the previously identified apparent correlation between reduced mortality and the very pronounced ban-related lowering of the black-smoke concentration. The third important finding was that in nonepidemic pre-ban seasons even large changes in the concentration of black smoke had no detectable effect on mortality rates. The reanalysis suggests that epidemiological studies exploring the effect of ambient particulate matter on mortality require improved tools allowing proper adjustment for epidemics and trends.« less

Sensitive gas analysis system on a microchip and application for on-site monitoring of NH3 in a clean room.

PubMed

Hiki, Shinichiro; Mawatari, Kazuma; Aota, Arata; Saito, Maki; Kitamori, Takehiko

2011-06-15

A portable, highly sensitive, and continuous ammonia gas monitoring system was developed with a microfluidic chip. The system consists of a main unit, a gas pumping unit, and a computer which serves as an operation console. The size of the system is 45 cm width × 30 cm depth × 30 cm height, and the portable system was realized. A highly efficient and stable extraction method was developed by utilizing an annular gas/liquid laminar flow. In addition, a stable gas/liquid separation method with a PTFE membrane was developed by arranging a fluidic network in three dimensions to achieve almost zero dead volume at the gas/liquid extraction part. The extraction rate was almost 100% with a liquid flow rate of 3.5 μL/min and a gas flow rate of 100 mL/min (contact time of ~15 ms), and the concentration factor was 200 times by calculating the NH(3) concentration (w/w unit) in the gas and liquid phases. Stable phase separation and detection was sustained for more than 3 weeks in an automated operation, which was sufficient for the monitoring application. The lower limit of detection calculated based on a signal-to-noise ratio of 3 was 84 ppt, which showed good detectability for NH(3) analysis. We believe that our system is a very powerful tool for gas analysis due to the advantages of portable size, high sensitivity, and continuous monitoring, and it is particularly useful in the semiconductor field.

One hundred and fifty years of sprint and distance running – Past trends and future prospects

PubMed Central

Weiss, Martin; Newman, Alexandra; Whitmore, Ceri; Weiss, Stephan

2016-01-01

Abstract Sprint and distance running have experienced remarkable performance improvements over the past century. Attempts to forecast running performances share an almost similarly long history but have relied so far on relatively short data series. Here, we compile a comprehensive set of season-best performances for eight Olympically contested running events. With this data set, we conduct (1) an exponential time series analysis and (2) a power-law experience curve analysis to quantify the rate of past performance improvements and to forecast future performances until the year 2100. We find that the sprint and distance running performances of women and men improve exponentially with time and converge at yearly rates of 4% ± 3% and 2% ± 2%, respectively, towards their asymptotic limits. Running performances can also be modelled with the experience curve approach, yielding learning rates of 3% ± 1% and 6% ± 2% for the women's and men's events, respectively. Long-term trends suggest that: (1) women will continue to run 10–20% slower than men, (2) 9.50 s over 100 m dash may only be broken at the end of this century and (3) several middle- and long-distance records may be broken within the next two to three decades. The prospects of witnessing a sub-2 hour marathon before 2100 remain inconclusive. Our results should be interpreted cautiously as forecasting human behaviour is intrinsically uncertain. The future season-best sprint and distance running performances will continue to scatter around the trends identified here and may yield unexpected improvements of standing world records. PMID:26088705

The effect of automated monitoring and real-time prompting on nurses' hand hygiene performance.

PubMed

Levchenko, Alexander I; Boscart, Veronique M; Fernie, Geoff R

2013-10-01

Adequate hand hygiene compliance by healthcare staff is considered an effective method to reduce hospital-acquired infections. The electronic system developed at Toronto Rehabilitation Institute automatically detects hand hygiene opportunities and records hand hygiene actions. It includes an optional visual hand hygiene status indication, generates real-time hand hygiene prompting signals, and enables automated monitoring of individual and aggregated hand hygiene performance. The system was installed on a complex continuous care unit at the entrance to 17 patient rooms and a utility room. A total of 93 alcohol gel and soap dispensers were instrumented and 14 nurses were provided with the personal wearable electronic monitors. The study included three phases with the system operating in three different modes: (1) an inactive mode during the first phase when hand hygiene opportunities and hand hygiene actions were recorded but prompting and visual indication functions were disabled, (2) only hand hygiene status indicators were enabled during the second phase, and (3) both hand hygiene status and real-time hand hygiene prompting signals were enabled during the third phase. Data collection was performed automatically during all of the three phases. The system indicated significantly higher hand hygiene activity rates and compliance during the third phase, with both hand hygiene indication and real-time prompting functions enabled. To increase the efficacy of the technology, its use was supplemented with individual performance reviews of the automatically collected data.

[Continuity of utilization of a levonorgestrel releasing contraceptive implant: prospective study in Belgium].

PubMed

Vekemans, M; Delvigne, A; Paesmans, M

1996-12-01

Since 1988 we inserted 760 sets of a subcutaneous hormonal contraceptive releasing levonorgestrel active for 5 years. The aim of the study was to investigate the continuation rates. We considered our first 612 insertions. The 5-year cumulative pregnancy rate was 3.7%. The continuation rates were high (50% of the implants remained in situ after 3 1/2 years). These rates increased with age, and were better with European than with non-European subjects (mainly Moroccan and Turkish women). Parity didn't influence. The rates increased over time, because more unhappy women soon came back compared to satisfied users. Removals were related to pregnancy wish, irregular blood loss, end of action, and various side effects. In a few cases untrained physicians removed the implants.

Neoadjuvant 5-FU or Capecitabine Plus Radiation With or Without Oxaliplatin in Rectal Cancer Patients: A Phase III Randomized Clinical Trial

PubMed Central

Yothers, Greg; O’Connell, Michael J.; Beart, Robert W.; Wozniak, Timothy F.; Pitot, Henry C.; Shields, Anthony F.; Landry, Jerome C.; Ryan, David P.; Arora, Amit; Evans, Lisa S.; Bahary, Nathan; Soori, Gamini; Eakle, Janice F.; Robertson, John M.; Moore, Dennis F.; Mullane, Michael R.; Marchello, Benjamin T.; Ward, Patrick J.; Sharif, Saima; Roh, Mark S.; Wolmark, Norman

2015-01-01

Background: National Surgical Adjuvant Breast and Bowel Project R-04 was designed to determine whether the oral fluoropyrimidine capecitabine could be substituted for continuous infusion 5-FU in the curative setting of stage II/III rectal cancer during neoadjuvant radiation therapy and whether the addition of oxaliplatin could further enhance the activity of fluoropyrimidine-sensitized radiation. Methods: Patients with clinical stage II or III rectal cancer undergoing preoperative radiation were randomly assigned to one of four chemotherapy regimens in a 2x2 design: CVI 5-FU or oral capecitabine with or without oxaliplatin. The primary endpoint was local-regional tumor control. Time-to-event endpoint distributions were estimated using the Kaplan-Meier method. Hazard ratios were estimated from Cox proportional hazard models. All statistical tests were two-sided. Results: Among 1608 randomized patients there were no statistically significant differences between regimens using 5-FU vs capecitabine in three-year local-regional tumor event rates (11.2% vs 11.8%), 5-year DFS (66.4% vs 67.7%), or 5-year OS (79.9% vs 80.8%); or for oxaliplatin vs no oxaliplatin for the three endpoints of local-regional events, DFS, and OS (11.2% vs 12.1%, 69.2% vs 64.2%, and 81.3% vs 79.0%). The addition of oxaliplatin was associated with statistically significantly more overall and grade 3–4 diarrhea (P < .0001). Three-year rates of local-regional recurrence among patients who underwent R0 resection ranged from 3.1 to 5.1% depending on the study arm. Conclusions: Continuous infusion 5-FU produced outcomes for local-regional control, DFS, and OS similar to those obtained with oral capecitabine combined with radiation. This study establishes capecitabine as a standard of care in the pre-operative rectal setting. Oxaliplatin did not improve the local-regional failure rate, DFS, or OS for any patient risk group but did add considerable toxicity. PMID:26374429

Preventive Efficacy and Safety of Rebamipide in Nonsteroidal Anti-Inflammatory Drug-Induced Mucosal Toxicity

PubMed Central

Kim, Jeong Ho; Park, Soo-Heon; Cho, Chul-Soo; Lee, Soo Teik; Yoo, Wan-Hee; Kim, Sung Kook; Kang, Young Mo; Rew, Jong Sun; Park, Yong-Wook; Lee, Soo Kon; Lee, Yong Chan; Park, Won; Lee, Don-Haeng

2014-01-01

Background/Aims The use of proton pump inhibitors or misoprostol is known to prevent the gastrointestinal complications of nonsteroidal anti-inflammatory drugs (NSAIDs). Rebamipide is known to increase the mucosal generation of prostaglandins and to eliminate free oxygen radicals, thus enhancing the protective function of the gastric mucosa. However, it is unknown whether rebamipide plays a role in preventing NSAID-induced gastropathy. The aim of this study was to determine the effectiveness of rebamipide compared to misoprostol in preventing NSAID-induced gastrointestinal complications in patients requiring continuous NSAID treatment. Methods We studied 479 patients who required continuous NSAID treatment. The patients were randomly assigned to groups that received 100 mg of rebamipide three times per day or 200 μg of misoprostol three times per day for 12 weeks. The primary endpoint of the analysis was the occurrence rate of gastric ulcers, as determined by endoscopy after 12 weeks of therapy. Results Of the 479 patients in the study, 242 received rebamipide, and 237 received misoprostol. Ultimately, 44 patients (18.6%) withdrew from the misoprostol group and 25 patients (10.3%) withdrew from the rebamipide group. There was a significant difference in withdrawal rate between the two groups (p=0.0103). The per protocol analysis set was not valid because of the dropout rate of the misoprostol group; thus, the intention to treat (ITT) analysis set is the main set for the efficacy analysis in this study. After 12 weeks, the occurrence rate of gastric ulcers was similar in the rebamipide and misoprostol groups (20.3% vs 21.9%, p=0.6497) according to ITT analysis. In addition, the therapeutic failure rate was similar in the rebamipide and misoprostol groups (13.6% vs 13.1%, p=0.8580). The total severity score of the gastrointestinal symptoms was significantly lower in the rebamipide group than in the misoprostol group (p=0.0002). The amount of antacid used was significantly lower in the rebamipide group than in the misoprostol group (p=0.0258). Conclusions Rebamipide can prevent gastric ulcers when used with NSAIDs and can decrease the gastrointestinal symptoms associated with NSAID administration. When the possibility of poor compliance and the potential adverse effects of misoprostol are considered, rebamipide appears to be a clinically effective and safe alternative. PMID:25071901

Preventive efficacy and safety of rebamipide in nonsteroidal anti-inflammatory drug-induced mucosal toxicity.

PubMed

Kim, Jeong Ho; Park, Soo-Heon; Cho, Chul-Soo; Lee, Soo Teik; Yoo, Wan-Hee; Kim, Sung Kook; Kang, Young Mo; Rew, Jong Sun; Park, Yong-Wook; Lee, Soo Kon; Lee, Yong Chan; Park, Won; Lee, Don-Haeng

2014-07-01

The use of proton pump inhibitors or misoprostol is known to prevent the gastrointestinal complications of nonsteroidal anti-inflammatory drugs (NSAIDs). Rebamipide is known to increase the mucosal generation of prostaglandins and to eliminate free oxygen radicals, thus enhancing the protective function of the gastric mucosa. However, it is unknown whether rebamipide plays a role in preventing NSAID-induced gastropathy. The aim of this study was to determine the effectiveness of rebamipide compared to misoprostol in preventing NSAID-induced gastrointestinal complications in patients requiring continuous NSAID treatment. We studied 479 patients who required continuous NSAID treatment. The patients were randomly assigned to groups that received 100 mg of rebamipide three times per day or 200 μg of misoprostol three times per day for 12 weeks. The primary endpoint of the analysis was the occurrence rate of gastric ulcers, as determined by endoscopy after 12 weeks of therapy. Of the 479 patients in the study, 242 received rebamipide, and 237 received misoprostol. Ultimately, 44 patients (18.6%) withdrew from the misoprostol group and 25 patients (10.3%) withdrew from the rebamipide group. There was a significant difference in withdrawal rate between the two groups (p=0.0103). The per protocol analysis set was not valid because of the dropout rate of the misoprostol group; thus, the intention to treat (ITT) analysis set is the main set for the efficacy analysis in this study. After 12 weeks, the occurrence rate of gastric ulcers was similar in the rebamipide and misoprostol groups (20.3% vs 21.9%, p=0.6497) according to ITT analysis. In addition, the therapeutic failure rate was similar in the rebamipide and misoprostol groups (13.6% vs 13.1%, p=0.8580). The total severity score of the gastrointestinal symptoms was significantly lower in the rebamipide group than in the misoprostol group (p=0.0002). The amount of antacid used was significantly lower in the rebamipide group than in the misoprostol group (p=0.0258). Rebamipide can prevent gastric ulcers when used with NSAIDs and can decrease the gastrointestinal symptoms associated with NSAID administration. When the possibility of poor compliance and the potential adverse effects of misoprostol are considered, rebamipide appears to be a clinically effective and safe alternative.

New techniques in television to provide research in three-dimensional real-time or near real-time imagery and reduced cost systems for teleconferencing and educational uses, part 1

NASA Technical Reports Server (NTRS)

Pao, Y. H.; Claspy, P.; Allen, J. E.; Merat, F.

1979-01-01

The results are presented of a continuing research and development program the objective of which is to develop a reduced bandwidth television system and a technique for television transmission of holograms. The result of the former is a variable frame rate television system, the operation of which was demonstrated for both black-and-white and color signals. This system employs a novel combination of the inexpensive mass storage capacity of a magnetic disc with the reliability of a digital system for time expansion and compression. Also reported are the results of a theoretical analysis and preliminary feasibility experiment of an innovative system for television transmission of holograms using relatively conventional TV equipment along with a phase modulated reference wave for production of the original interference pattern.

Breast cancer tumour growth modelling for studying the association of body size with tumour growth rate and symptomatic detection using case-control data.

PubMed

Abrahamsson, Linda; Czene, Kamila; Hall, Per; Humphreys, Keith

2015-08-21

A large body size is associated with larger breast cancer tumours at diagnosis. Standard regression models for tumour size at diagnosis are not sufficient for unravelling the mechanisms behind the association. Using Swedish case-control data, we identified 1352 postmenopausal women with incident invasive breast cancer diagnosed between 1993 and 1995. We used a novel continuous tumour growth model, which models tumour sizes at diagnosis through three submodels: for tumour growth, time to symptomatic detection, and screening sensitivity. Tumour size at other time points is thought of as a latent variable. We quantified the relationship between body size with tumour growth and time to symptomatic detection. High body mass index and large breast size are, respectively, significantly associated with fast tumour growth rate and delayed time to symptomatic detection (combined P value = 5.0 × 10(-5) and individual P values = 0.089 and 0.022). We also quantified the role of mammographic density in screening sensitivity. The times at which tumours will be symptomatically detected may vary substantially between women with different breast sizes. The proposed tumour growth model represents a novel and useful approach for quantifying the effects of breast cancer risk factors on tumour growth and detection.

Real-time traffic sign detection and recognition

NASA Astrophysics Data System (ADS)

Herbschleb, Ernst; de With, Peter H. N.

2009-01-01

The continuous growth of imaging databases increasingly requires analysis tools for extraction of features. In this paper, a new architecture for the detection of traffic signs is proposed. The architecture is designed to process a large database with tens of millions of images with a resolution up to 4,800x2,400 pixels. Because of the size of the database, a high reliability as well as a high throughput is required. The novel architecture consists of a three-stage algorithm with multiple steps per stage, combining both color and specific spatial information. The first stage contains an area-limitation step which is performance critical in both the detection rate as the overall processing time. The second stage locates suggestions for traffic signs using recently published feature processing. The third stage contains a validation step to enhance reliability of the algorithm. During this stage, the traffic signs are recognized. Experiments show a convincing detection rate of 99%. With respect to computational speed, the throughput for line-of-sight images of 800×600 pixels is 35 Hz and for panorama images it is 4 Hz. Our novel architecture outperforms existing algorithms, with respect to both detection rate and throughput

A finite nonlinear hyper-viscoelastic model for soft biological tissues.

PubMed

Panda, Satish Kumar; Buist, Martin Lindsay

2018-03-01

Soft tissues exhibit highly nonlinear rate and time-dependent stress-strain behaviour. Strain and strain rate dependencies are often modelled using a hyperelastic model and a discrete (standard linear solid) or continuous spectrum (quasi-linear) viscoelastic model, respectively. However, these models are unable to properly capture the materials characteristics because hyperelastic models are unsuited for time-dependent events, whereas the common viscoelastic models are insufficient for the nonlinear and finite strain viscoelastic tissue responses. The convolution integral based models can demonstrate a finite viscoelastic response; however, their derivations are not consistent with the laws of thermodynamics. The aim of this work was to develop a three-dimensional finite hyper-viscoelastic model for soft tissues using a thermodynamically consistent approach. In addition, a nonlinear function, dependent on strain and strain rate, was adopted to capture the nonlinear variation of viscosity during a loading process. To demonstrate the efficacy and versatility of this approach, the model was used to recreate the experimental results performed on different types of soft tissues. In all the cases, the simulation results were well matched (R 2 ⩾0.99) with the experimental data. Copyright © 2018 Elsevier Ltd. All rights reserved.

Initiation & completion rates of hepatitis A vaccination among US pediatric populations born between 2005 and 2009.

PubMed

Weiss, Thomas; Zhang, Dongmu; Borse, Nagesh N; Walter, Emmanuel B

2015-11-27

To estimate hepatitis A vaccine series initiation and completion rates, assess time to vaccination, identify missed opportunities for the hepatitis A vaccine series, and examine factors associated with hepatitis A vaccine series initiation and completion. We conducted a retrospective, observational study using three healthcare claims databases separately. The study population was comprised of children born between years 2005 and 2009 that were continuously enrolled for at least three and a half years from the date of birth. Every child was followed from date of birth for three and a half years for hepatitis A vaccination. There were 93,735 eligible children from Clinformatics Data Mart, 202,513 from MarketScan Commercial, and 207,545 from MarketScan Medicaid. The overall hepatitis A vaccine series initiation rate was 63.8-79.4% and completion rate was 45.1-66.8% across the three databases. About 62.8-90.1% of the children who never initiated hepatitis A vaccine had at least one well visit from 1 year to three and a half years old. Children were more likely to initiate and complete the hepatitis A vaccine series if they were from more recent birth cohorts, from states with a hepatitis A vaccination recommendation prior to the ACIP universal recommendation, from states with daycare/school entry requirements, were enrolled in an HMO health plan, had pediatricians as primary providers, had more doctor's office/well visits and received MMR/Varicella vaccines. In this study, approximately one in every three to five children remained unvaccinated against hepatitis A. Although the hepatitis A vaccine series initiation and completion improved from 2005 to 2009, vaccine coverage has stabilized in recent years. It is important for providers to identify every opportunity for hepatitis A vaccination and to assure that children get protection from this vaccine-preventable disease. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

To continue, modify or relinquish driving: findings from a longitudinal study of healthy ageing.

PubMed

Unsworth, Carolyn A; Wells, Yvonne; Browning, Colette; Thomas, Shane A; Kendig, Hal

2007-01-01

The number and proportion of drivers among people entering later life continues to rise. More information on patterns of driving for older adults is required to improve service provision and traffic planning. To map the changes in driving status for a sample of drivers aged 65 years or older over the period 1994-2000, and to identify factors associated with older people continuing, modifying or relinquishing their status as drivers. The 752 participants were drawn from the Melbourne Longitudinal Studies on Healthy Ageing (MELSHA) program, a longitudinal study of people aged 65 years and older living in the community. Participants were interviewed or contacted for follow-up in 1994, 1996, 1998 and 2000 on a range of topics including their health, functional independence and driving status. Although the number of recent drivers was smaller as participants died or were admitted to nursing homes over the 6-year data collection period, relatively few participants relinquished driving while remaining in the community. Many drivers reported modifying their driving habits over time, including decisions to restrict their driving to their local area during daylight only. Relationships were explored between driving status and the key variables of age, gender, marital status, instrumental activities of daily living (IADL) independence and self-rated measures of income, health, eyesight and hearing. Multivariate analyses indicated that drivers were more likely to modify their driving habits if they were older, dependent in IADL, and rated their eyesight as poor. Similar factors predicted relinquishing driving, but in addition, women were three times more likely to relinquish driving than men (even when health and disability were taken into account) and people who rated their incomes as 'comfortable' were more likely to relinquish driving than those with lower incomes. This study confirmed previous evidence that older drivers self-regulate by modifying their driving behavior as they age. However, since few drivers voluntarily relinquish driving, further research is required to identify ways of supporting older drivers to continue to drive safely. Copyright 2007 S. Karger AG, Basel.

Retaining Traditionally Hard to Reach Participants: Lessons Learned from Three Childhood Obesity Studies

PubMed Central

Buscemi, Joanna; Blumstein, Lara; Kong, Angela; Stolley, Melinda L.; Schiffer, Linda; Odoms-Young, Angela; Bittner, Cheryl; Fitzgibbon, Marian L.

2015-01-01

Retaining underserved populations, particularly low-income and/or minority participants in research trials, presents a unique set of challenges. In this paper, we describe initial retention strategies and enhanced retention strategies over time across three childhood obesity prevention trials. Hip Hop to Health Jr. (HH) was a randomized controlled trial (RCT) testing a preschool-based obesity prevention intervention among predominately African-American children. Retention was 89% at 14 weeks, 71% at 1-year, and 73% at 2-year follow up. Primary retention strategies for HH included: 1) collaboration with a community-based organization to enhance program credibility; 2) continuity of data collection locations; 3) collecting detailed contact information and provision of monetary compensation; and 4) developing a detailed tracking/search protocol. In a follow-up trial, Hip-Hop to Health Jr. Obesity Prevention Effectiveness Trial (HH Effectiveness), 95% of participants completed assessment at 14 weeks and 88% completed assessment at 1 year. For this trial, we emphasized staffing continuity in order to enhance participant relationship building and required data collection staff to have relevant community service experience. In a third study, we assessed dietary quality among participants in the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) across three time points following the WIC food package shift instituted nationally in 2009. Retention rates were 91% at 12 months and 89% at 18 months. For our WIC study, we augmented retention by developing a home data collection protocol and increased focus on staff diversity training. We conclude with a summary of key strategies and suggestions for future research. PMID:25847577

Investigation of Poultry Waste for Anaerobic Digestion: A Case Study

NASA Astrophysics Data System (ADS)

Salam, Christopher R.

Anaerobic Digestion (AD) is a biological conversion technology which is being used to produce bioenergy all over the world. This energy is created from biological feedstocks, and can often use waste products from various food and agricultural processors. Biogas from AD can be used as a fuel for heating or for co-generation of electricity and heat and is a renewable substitute to using fossil fuels. Nutrient recycling and waste reduction are additional benefits, creating a final product that can be used as a fertilizer in addition to energy benefits. This project was conducted to investigate the viability of three turkey production wastes as AD feedstock: two turkey litters and a material separated from the turkey processing wastewater using dissolved air flotation (DAF) process. The DAF waste contained greases, oils and other non-commodity portions of the turkey. Using a variety of different process methods, types of bacteria, loading rates and food-to-microorganism ratios, optimal loading rates for the digestion of these three materials were obtained. In addition, the co-digestion of these materials revealed additional energy benefits. In this study, batch digestion tests were carried out to treat these three feedstocks, using mesophilic and thermophilic bacteria, using loading rates of 3 and 6 gVS/L They were tested separately and also as a mixture for co-digestion. The batch reactor used in this study had total and working volumes of 1130 mL and 500 mL, respectively. The initial organic loading was set to be 3 gVS/L, and the food to microorganism ratio was either 0.6 or 1.0 for different treatments based on the characteristics of each material. Only thermophilic (50 +/- 2ºC) temperatures were tested for the litter and DAF wastes in continuous digestion, but mesophilic and thermophilic batch digestion experiments were conducted. The optimum digestion time for all experiments was 14 days. The biogas yields of top litter, mixed litter, and DAF waste under mesophilic batch conditions all at 3 gVS/L loading were determined to be 148.6 +/- 7.82, 176.5 +/- 11.1 and 542.0 +/- 37.9 mL/ gVS, respectively and were 201.9 +/- 10.0, 210.4 +/- 29.3, and 419.3 +/- 12.1 mL/gVS, respectively, for initial loading of 6 gVS/L. Under thermophilic batch conditions, the top litter, mixed litter, and DAF waste had the biogas yields of 255.3 +/- 7.9, 313.4 +/- 30.1and 297.4 +/- 33.8 mL/gVS for loading rate of 3 gVS/L and 233.8 +/- 45.3, 306.5 +/- 11.8 and 185.1 +/- 0.85 mL/gVS for loading rate of 6 gVS/L. The biogas yields from co-digestion of the mixed litter and DAF waste at 3 gVS/L were 461.8 +/- 41.3 mL/gVS under thermophilic conditions. The results from batch anaerobic digestion tests were then used for designing continuous digestion experiments. All the continuous digestion experiments were conducted by using an Anaerobic Phase Solids (APS) digester system operated at a thermophilic temperature. The total volume of the continuous digester system was 4.8 L and the working volume was around 4.4 L. The APS digester system had two hydrolysis reactors and one biogasification reactor. Feedstock was loaded into the hydrolysis reactors in batches. The feedstock digestion time was 14 days and the average organic loading rate (OLR) of the system was 3 gVS/L/day. The experiment has three distinct feedstock stages, first with turkey litter waste, a co-digestion of DAF and turkey litter waste, followed by DAF waste. The biogas yields were determined to be 305.2 +/- 70.6 mL/gVS/d for turkey mixed litter, 455.8 +/- 77.2 mL/gVS/d during the mixture of mixed litter and DAF waste, and 382.0 +/- 39.6 mL/gVS for DAF waste. The biogas yields from the thermophilic batch test yields compare with that of the continuous digester yields. For experiments utilizing turkey litter, batch tests yielded 313.4 +/- 30.1mL/gVS biogas and 305.2 +/- 70.6 mL/gVS/d for continuous experiments. For experiments using codigestion of turkey litter and DAF waste, batches yielded 461.8 +/- 41.3 mL/gVS biogas comparing well to continuous digester operation that yielded 455.8 +/- 77.2 mL/gVS/d. It was mainly in the case for DAF that batch vs. continuous digester testing yielded a significant difference in performance. For experiments using DAF waste, batches yielded 297.4 +/- 33.8 mL/gVS biogas and continuous digester operation yielded 455.8 +/- 77.2 mL/gVS/d. For a case study on the APS digester system, mesophilic DAF waste was chosen as the optimum substrate. Using this material and reactor condition, a case study was built using provided information and experimental results to build a simulation. A reactor site needed to process 11,800 kgVS of DAF waste would require 4,800 m3 of tank volume, and use nearly 4,000 m3 as working volume. This reactor was modeled after a 2 stage APS reactor, with 2 hydrolysis reactors and 1 biogasification reactor, and had a 14 day retention time and a 3 gVS/L/d organic loading rate. The expected biogas output was 550 mL/gVS, and expected waste reduction was 20%. The reactor would produce 7,113 m3/d of biogas, and would be burned for 127,223 MJ/d.

Estimating latent time of maturation and survival costs of reproduction in continuous time from capture-recapture data

USGS Publications Warehouse

Ergon, T.; Yoccoz, N.G.; Nichols, J.D.; Thomson, David L.; Cooch, Evan G.; Conroy, Michael J.

2009-01-01

In many species, age or time of maturation and survival costs of reproduction may vary substantially within and among populations. We present a capture-mark-recapture model to estimate the latent individual trait distribution of time of maturation (or other irreversible transitions) as well as survival differences associated with the two states (representing costs of reproduction). Maturation can take place at any point in continuous time, and mortality hazard rates for each reproductive state may vary according to continuous functions over time. Although we explicitly model individual heterogeneity in age/time of maturation, we make the simplifying assumption that death hazard rates do not vary among individuals within groups of animals. However, the estimates of the maturation distribution are fairly robust against individual heterogeneity in survival as long as there is no individual level correlation between mortality hazards and latent time of maturation. We apply the model to biweekly capture?recapture data of overwintering field voles (Microtus agrestis) in cyclically fluctuating populations to estimate time of maturation and survival costs of reproduction. Results show that onset of seasonal reproduction is particularly late and survival costs of reproduction are particularly large in declining populations.

Return of spontaneous Circulation Is Not Affected by Different Chest Compression Rates Superimposed with Sustained Inflations during Cardiopulmonary Resuscitation in Newborn Piglets

PubMed Central

Li, Elliott S.; Cheung, Po-Yin; Lee, Tze-Fun; Lu, Min; O'Reilly, Megan

2016-01-01

Objective Recently, sustained inflations (SI) during chest compression (CC) have been suggested as an alternative to the current approach during neonatal resuscitation. However, the optimal rate of CC during SI has not yet been established. Our aim was to determine whether different CC rates during SI reduce time to return of spontaneous circulation (ROSC) and improve hemodynamic recovery in newborn piglets with asphyxia-induced bradycardia. Intervention and measurements Term newborn piglets were anesthetized, intubated, instrumented and exposed to 45-min normocapnic hypoxia followed by asphyxia. Resuscitation was initiated when heart rate decreased to 25% of baseline. Piglets were randomized into three groups: CC superimposed by SI at a rate of 90 CC per minute (SI+CC 90, n = 8), CC superimposed by SI at a rate of 120 CC per minute (SI+CC 120, n = 8), or a sham group (n = 6). Cardiac function, carotid blood flow, cerebral oxygenation and respiratory parameters were continuously recorded throughout the experiment. Main results Both treatment groups had similar time of ROSC, survival rates, hemodynamic and respiratory parameters during cardiopulmonary resuscitation. The hemodynamic recovery in the subsequent 4h was similar in both groups and was only slightly lower than sham-operated piglets at the end of experiment. Conclusion Newborn piglets resuscitated by SI+CC 120 did not show a significant advantage in ROSC, survival, and hemodynamic recovery as compared to those piglets resuscitated by SI+CC 90. PMID:27304210

Comparison of Physiological and Perceptual Responses Between Continuous and Intermittent Cycling

PubMed Central

Brasil, Roxana M.; Barreto, Ana C.; Nogueira, Leandro; Santos, Edil; Novaes, Jefferson S.; Reis, Victor M.

2011-01-01

The present study tested the hypothesis that the exercise protocol (continuous vs. intermittent) would affect the physiological response and the perception of effort during aquatic cycling. Each protocol was divided on four stages. Heart rate, arterial blood pressure, blood lactate concentration, central and peripheral rate of perceived exertion were collected in both protocols in aquatic cycling in 10 women (values are mean ± SD): age=32.8 ± 4.8 years; height=1.62 ± 0.05 cm; body mass=61.60 ± 5.19 kg; estimated body fat=27.13 ± 4.92%. Protocols were compared through two way ANOVA with Scheffé’s post-hoc test and the test of Mann- Whitney for rate of perceived exertion with α=0.05. No systematic and consistent differences in heart rate, arterial blood pressure, double product and blood lactate concentration were found between protocols. On the other hand, central rate of perceived exertion was significantly higher at stage four during continuous protocol compared with intermittent protocol (p=0.01), while the peripheral rate of perceived exertion presented higher values at stages three (p=0.02) and four (p=0.00) in the continuous protocol when compared to the results found in intermittent protocol. These findings suggest that although the aquatic cycling induces similar physiologic demands in both protocols, the rate of perceived exertion may vary according to the continuous vs. intermittent nature of the exercise. PMID:23487483

The Pringle maneuver reduces the infusion rate of rocuronium required to maintain surgical muscle relaxation during hepatectomy.

PubMed

Kajiura, Akira; Nagata, Osamu; Sanui, Masamitsu

2018-04-27

We investigated the continuous infusion rates of rocuronium necessary to obtain the surgical muscle relaxation before, during, and after the Pringle maneuver on patients who underwent hepatectomy. Fifteen patients were induced by total intravenous anesthesia with propofol. After obtaining the calibration of acceleromyography, the patient was intubated with rocuronium 0.6 mg/kg. Fifteen minutes after initial rocuronium injection, the continuous infusion was started at 7.5 µg/kg/min. The infusion rate was adjusted every 15 min so that the first twitch height (% T1) might become from 3 to 10% of control. The infusion rates at the time when the state of surgical muscle relaxation was achieved for more than 15 min were recorded before, during and after the Pringle maneuver. The 25% recovery time was measured after discontinuing the continuous infusion. The infusion rate of rocuronium before, during, and after the Pringle maneuver was 7.2 ± 1.8, 4.2 ± 1.4, and 4.7 ± 1.5 µg/kg/min (mean ± SD), respectively. The rocuronium infusion rate during the Pringle maneuver was decreased about 40% compared to that before this maneuver, and that after completion of the Pringle maneuver was not recovered to that before the Pringle maneuver. The 25% recovery time was 20 ± 7 min. In case of continuous administration of rocuronium during surgery performing the Pringle maneuver, it was considered necessary to regulate the administration of rocuronium using muscle relaxant monitoring in order to deal with the decrease in muscle relaxant requirement by the Pringle maneuver.

Intensity of Renal Support in Critically Ill Patients with Acute Kidney Injury

PubMed Central

2008-01-01

BACKGROUND The optimal intensity of renal-replacement therapy in critically ill patients with acute kidney injury is controversial. METHODS We randomly assigned critically ill patients with acute kidney injury and failure of at least one nonrenal organ or sepsis to receive intensive or less intensive renal-replacement therapy. The primary end point was death from any cause by day 60. In both study groups, hemodynamically stable patients underwent intermittent hemodialysis, and hemodynamically unstable patients underwent continuous venovenous hemodiafiltration or sustained low-efficiency dialysis. Patients receiving the intensive treatment strategy underwent intermittent hemodialysis and sustained low-efficiency dialysis six times per week and continuous venovenous hemodiafiltration at 35 ml per kilogram of body weight per hour; for patients receiving the less-intensive treatment strategy, the corresponding treatments were provided thrice weekly and at 20 ml per kilogram per hour. RESULTS Baseline characteristics of the 1124 patients in the two groups were similar. The rate of death from any cause by day 60 was 53.6% with intensive therapy and 51.5% with less-intensive therapy (odds ratio, 1.09; 95% confidence interval, 0.86 to 1.40; P = 0.47). There was no significant difference between the two groups in the duration of renalreplacement therapy or the rate of recovery of kidney function or nonrenal organ failure. Hypotension during intermittent dialysis occurred in more patients randomly assigned to receive intensive therapy, although the frequency of hemodialysis sessions complicated by hypotension was similar in the two groups. CONCLUSIONS Intensive renal support in critically ill patients with acute kidney injury did not decrease mortality, improve recovery of kidney function, or reduce the rate of nonrenal organ failure as compared with less-intensive therapy involving a defined dose of intermittent hemodialysis three times per week and continuous renal-replacement therapy at 20 ml per kilogram per hour. (ClinicalTrials.gov number, NCT00076219.) PMID:18492867

Quantification aspects of constant pressure (ultra) high pressure liquid chromatography using mass-sensitive detectors with a nebulizing interface.

PubMed

Verstraeten, M; Broeckhoven, K; Lynen, F; Choikhet, K; Landt, K; Dittmann, M; Witt, K; Sandra, P; Desmet, G

2013-01-25

The present contribution investigates the quantitation aspects of mass-sensitive detectors with nebulizing interface (ESI-MSD, ELSD, CAD) in the constant pressure gradient elution mode. In this operation mode, the pressure is controlled and maintained at a set value and the liquid flow rate will vary according to the inverse mobile phase viscosity. As the pressure is continuously kept at the allowable maximum during the entire gradient run, the average liquid flow rate is higher compared to that in the conventional constant flow rate operation mode, thus shortening the analysis time. The following three mass-sensitive detectors were investigated: mass spectrometry detector (MS), evaporative light scattering detector (ELSD) and charged aerosol detector (CAD) and a wide variety of samples (phenones, polyaromatic hydrocarbons, wine, cocoa butter) has been considered. It was found that the nebulizing efficiency of the LC-interfaces of the three detectors under consideration changes with the increasing liquid flow rate. For the MS, the increasing flow rate leads to a lower peak area whereas for the ELSD the peak area increases compared to the constant flow rate mode. The peak area obtained with a CAD is rather insensitive to the liquid flow rate. The reproducibility of the peak area remains similar in both modes, although variation in system permeability compromises the 'long-term' reproducibility. This problem can however be overcome by running a flow rate program with an optimized flow rate and composition profile obtained from the constant pressure mode. In this case, the quantification remains reproducibile, despite any occuring variations of the system permeability. Furthermore, the same fragmentation pattern (MS) has been found in the constant pressure mode compared to the customary constant flow rate mode. Copyright © 2012 Elsevier B.V. All rights reserved.

Hormonal and intrauterine methods for contraception for women aged 25 years and younger.

PubMed

Krashin, Jamie; Tang, Jennifer H; Mody, Sheila; Lopez, Laureen M

2015-08-17

Women between the ages of 15 and 24 years have high rates of unintended pregnancy; over half of women in this age group want to avoid pregnancy. However, women under age 25 years have higher typical contraceptive failure rates within the first 12 months of use than older women. High discontinuation rates may also be a problem in this population. Concern that adolescents and young women will not find hormonal or intrauterine contraceptives acceptable or effective might deter healthcare providers from recommending these contraceptive methods. To compare the contraceptive failure (pregnancy) rates and to examine the continuation rates for hormonal and intrauterine contraception among young women aged 25 years and younger. We searched until 4 August 2015 for randomized controlled trials (RCTs) that compared hormonal or intrauterine methods of contraception in women aged 25 years and younger. Computerized databases included the Cochrane Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, POPLINE, CINAHL, and LILACS. We also searched for current trials via ClinicalTrials.gov and the International Clinical Trials Registry Platform (ICTRP). We considered RCTs in any language that reported the contraceptive failure rates for hormonal or intrauterine contraceptive methods, when compared with another contraceptive method, for women aged 25 years and younger. The other contraceptive method could have been another intrauterine contraceptive, another hormonal contraceptive or different dose of the same method, or a non-hormonal contraceptive. Treatment duration must have been at least three months. Eligible trials had to include the primary outcome of contraceptive failure rate (pregnancy). The secondary outcome was contraceptive continuation rate. One author conducted the primary data extraction and entered the information into Review Manager. Another author performed an independent data extraction and verified the initial entry. For dichotomous outcomes, we computed the Mantel-Haenszel odds ratio (OR) with 95% confidence interval (CI). Because of disparate interventions and outcome measures, we did not conduct meta-analysis. Five trials met the inclusion criteria. The studies included a total of 1503 women, with a mean of 301 participants. The trials compared the following contraceptives: combined oral contraceptive (COC) versus transdermal contraceptive patch, vaginal contraceptive ring, or levonorgestrel intrauterine system 20 µg/day (LNG-IUS 20); LNG-IUS 12 µg/day (LNG-IUS 12) versus LNG-IUS 16 µg/day (LNG-IUS 16); and LNG-IUS 20 versus the copper T380A intrauterine device (IUD). In the trials comparing two different types of methods, the study arms did not differ significantly for contraceptive efficacy or continuation. The sample sizes were small for two of those studies. The only significant outcome was that a COC group had a higher proportion of women who discontinued for 'other personal reasons' compared with the group assigned to the LNG-IUS 20 (OR 0.27, 95% CI 0.09 to 0.85), which may have little clinic relevance. The trial comparing LNG-IUS 12 versus LNG-IUS 16 showed similar efficacy over one and three years. In three trials that examined different LNG-IUS, continuation was at least 75% at 6 to 36 months. We considered the overall quality of evidence to be moderate to low. Limitations were due to trial design or limited reporting. Different doses in the LNG-IUS did not appear to influence efficacy over three years. In another study, continuation of the LNG-IUS appeared at least as high as that for the COC. The current evidence was insufficient to compare efficacy and continuation rates for hormonal and intrauterine contraceptive methods in women aged 25 years and younger.

Wastewater microalgal production, nutrient removal and physiological adaptation in response to changes in mixing frequency.

PubMed

Sutherland, Donna L; Turnbull, Matthew H; Broady, Paul A; Craggs, Rupert J

2014-09-15

Laminar flows are a common problem in high rate algal ponds (HRAP) due to their long channels and gentle mixing by a single paddlewheel. Sustained laminar flows may modify the amount of light microalgal cells are exposed to, increase the boundary layer between the cell and the environment and increase settling out of cells onto the pond bottom. To date, there has been little focus on the effects of the time between mixing events (frequency of mixing) on the performance of microalgae in wastewater treatment HRAPs. This paper investigates the performance of three morphologically distinct microalgae in wastewater treatment high rate algal mesocosms operated at four different mixing frequencies (continuous, mixed every 45 min, mixed every 90 min and no mixing). Microalgal performance was measured in terms of biomass concentration, nutrient removal efficiency, light utilisation and photosynthetic performance. Microalgal biomass increased significantly with increasing mixing frequency for the two colonial species but did not differ for the single celled species. All three species were more efficient at NH4-N uptake as the frequency of mixing increased. Increased frequency of mixing supported larger colonies with improved harvest-ability by gravity but at the expense of efficient light absorption and maximum rate of photosynthesis. However, maximum quantum yield was highest in the continuously mixed cultures due to higher efficiency of photosynthesis under light limited conditions. Based on these results, higher microalgal productivity, improved wastewater treatment and better gravity based harvest-ability can be achieved with the inclusion of more mixing points and reduced laminar flows in full-scale HRAP. Copyright © 2014 Elsevier Ltd. All rights reserved.

Comparison of Acute Physiological and Psychological Responses Between Moderate Intensity Continuous Exercise and three Regimes of High Intensity Training.

PubMed

Green, Nicole; Wertz, Timothy; LaPorta, Zachary; Mora, Adam; Serbas, Jasmine; Astorino, Todd A

2017-07-19

High intensity interval training (HIIT) elicits similar physiological adaptations as moderate intensity continuous training (MICT) despite less time commitment. However, there is debate whether HIIT is more aversive than MICT. This study compared physiological and perceptual responses between MICT and three regimes of HIIT. Nineteen active adults (age = 24.0 ± 3.3 yr) unfamiliar with HIIT initially performed ramp exercise to exhaustion to measure maximal oxygen uptake (VO2 max) and determine workload for subsequent sessions, whose order was randomized. Sprint interval training (SIT) consisted of six 20 s bouts of "all-out" cycling at 140% of maximum watts (Wmax). Low volume (HIITLV) and high volume HIIT (HIITHV) consisted of eight 60 s bouts at 85% Wmax and six 2 min bouts at 70% Wmax, respectively. MICT consisted of 25 min at 40% Wmax. Across regimes, work was not matched. Heart rate, VO2, blood lactate concentration (BLa), affect, and rating of perceived exertion (RPE) were assessed during exercise. Ten minutes post-exercise, Physical Activity Enjoyment (PACES) was measured via a survey. Results revealed significantly higher (p<0.05) VO2, heart rate, BLa, and RPE in SIT, HIITLV, and HIITHV versus MICT. Despite a decline in affect during exercise (p<0.01) and significantly lower affect (p<0.05) during all HIIT regimes versus MICT at 50, 75, and 100 % of session duration, PACES was similar across regimes (p=0.65) although it was higher in women (p=0.03). Findings from healthy adults unaccustomed to interval training demonstrate that HIIT and SIT are perceived as enjoyable as MICT despite being more aversive.

Caesarean Section in Peru: Analysis of Trends Using the Robson Classification System

PubMed Central

2016-01-01

Introduction Cesarean section rates continue to increase worldwide while the reasons appear to be multiple, complex and, in many cases, country specific. Over the last decades, several classification systems for caesarean section have been created and proposed to monitor and compare caesarean section rates in a standardized, reliable, consistent and action-oriented manner with the aim to understand the drivers and contributors of this trend. The aims of the present study were to conduct an analysis in the three Peruvian geographical regions to assess levels and trends of delivery by caesarean section using the Robson classification for caesarean section, identify the groups of women with highest caesarean section rates and assess variation of maternal and perinatal outcomes according to caesarean section levels in each group over time. Material and Methods Data from 549,681 pregnant women included in the Peruvian Perinatal Information System database from 43 maternal facilities in three Peruvian geographical regions from 2000 and 2010 were studied. The data were analyzed using the Robson classification and women were studied in the ten groups in the classification. Cochran-Armitage test was used to evaluate time trends in the rates of caesarean section rates and; logistic regression was used to evaluate risk for each classification. Results The caesarean section rate was 27% and a yearly increase in the overall caesarean section rates from 2000 to 2010 from 23.5% to 30% (time trend p<0.001) was observed. Robson groups 1, 3 (nulliparous and multiparas, respectively, with a single cephalic term pregnancy in spontaneous labour), 5 (multiparas with a previous uterine scar with a single, cephalic, term pregnancy) and 7 (multiparas with a single breech pregnancy with or without previous scars) showed an increase in the caesarean section rates over time. Robson groups 1 and 3 were significantly associated with stillbirths (OR 1.43, CI95% 1.17–1.72; OR 3.53, CI95% 2.95–4.2) and maternal mortality (OR 3.39, CI95% 1.59–7.22; OR 8.05, CI95% 3.34–19.41). Discussion The caesarean section rates increased in the last years as result of increased CS in groups with spontaneous labor and in-group of multiparas with a scarred uterus. Women included in groups 1 y 3 were associated to maternal perinatal complications. Women with previous cesarean section constitute the most important determinant of overall cesarean section rates. The use of Robson classification becomes an useful tool for monitoring cesarean section in low human development index countries. PMID:26840693

Short-term changes in running mechanics and foot strike pattern after introduction to minimalistic footwear.

PubMed

Willson, John D; Bjorhus, Jordan S; Williams, D S Blaise; Butler, Robert J; Porcari, John P; Kernozek, Thomas W

2014-01-01

Minimalistic footwear has garnered widespread interest in the running community, based largely on the premise that the footwear may reduce certain running-related injury risk factors through adaptations in running mechanics and foot strike pattern. To examine short-term adaptations in running mechanics among runners who typically run in conventional cushioned heel running shoes as they transition to minimalistic footwear. A 2-week, prospective, observational study. A movement science laboratory. Nineteen female runners with a rear foot strike (RFS) pattern who usually train in conventional running shoes. The participants trained for 20 minutes, 3 times per week for 2 weeks by using minimalistic footwear. Three-dimensional lower extremity running mechanics were analyzed before and after this 2-week period. Hip, knee, and ankle joint kinematics at initial contact; step length; stance time; peak ankle joint moment and joint work; impact peak; vertical ground reaction force loading rate; and foot strike pattern preference were evaluated before and after the intervention. The knee flexion angle at initial contact increased 3.8° (P < .01), but the ankle and hip flexion angles at initial contact did not change after training. No changes in ankle joint kinetics or running temporospatial parameters were observed. The majority of participants (71%), before the intervention, demonstrated an RFS pattern while running in minimalistic footwear. The proportion of runners with an RFS pattern did not decrease after 2 weeks (P = .25). Those runners who chose an RFS pattern in minimalistic shoes experienced a vertical loading rate that was 3 times greater than those who chose to run with a non-RFS pattern. Few systematic changes in running mechanics were observed among participants after 2 weeks of training in minimalistic footwear. The majority of the participants continued to use an RFS pattern after training in minimalistic footwear, and these participants experienced higher vertical loading rates. Continued exposure to these greater loading rates may have detrimental effects over time. Copyright © 2014 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.

Maternal physical activity mode and fetal heart outcome.

PubMed

May, Linda E; Suminski, Richard R; Berry, Andrew; Langaker, Michelle D; Gustafson, Kathleen M

2014-07-01

Maternal leisure-time physical activity (LTPA) improves cardiac autonomic function in the fetus. The specific physical activity attributes (e.g., mode) that produce this benefit are not well understood. To determine if more time spent performing non-continuous LTPA during pregnancy is significantly associated with lower fetal heart rate (HR) and increased heart rate variability (HRV). This paper presents a retrospective analysis of previously reported data. Fetal magnetocardiograms (MCG) were recorded from 40 pregnant women at 36-wk gestational age. Metrics of fetal HR and HRV, self-reported min of continuous and non-continuous LTPA performed during the 3-months preceding the 36-wk assessment point and covariates (maternal weight change pre to 36-wk, age, and resting HR and fetal activity state during MCG recordings. Positive correlations were significant (p<0.05) between min of continuous LTPA, the time domain metrics that describe fetal overall HRV, short-term HRV and a frequency domain metric that reflects vagal activity. Time spent in non-continuous LTPA was positively correlated (p<0.05) with two HRV metrics that reflect fetal overall HRV. In the multiple regression analyses, minutes of non-continuous LTPA remained associated with fetal vagal activity (p<0.05) and the relationships between minutes of non-continuous LTPA and fetal overall HRV (p<0.005) persisted. These data suggest non-continuous physical activity provides unique benefits to the fetal autonomic nervous system that may give the fetus an adaptive advantage. Further studies are needed to understand the physiological mechanisms and long-term health effects of physical activity (both non-continuous and continuous) performed during pregnancy to both women and their offspring. Copyright © 2014 Elsevier Ltd. All rights reserved.

THE EFFECT OF OPENING WINDOWS ON AIR CHANGE RATES IN TWO HOMES

EPA Science Inventory

Over 300 air change rate experiments were completed in two occupied residences: a two-story detached house in Redwood City, CA and a three-story townhouse in Reston, VA. A continuous monitor was used to measure the decay of sulfur hexafluoride tracer gas over periods of 1 to 1...

Soil property changes during loblolly pine production

Treesearch

R. Wayne Skaggs; Devendra M. Amatya; G.M. Chescheir; Christine D. Blanton

2006-01-01

Three watersheds, each approximately 25 ha, were instrumented to measure and record drainage rate, water table depth, rainfall and meteorological data. Data continuously collected on the site since 1988 include response of hydrologic and water quality variables for nearly all growth stages of a Loblolly pine plantation. Data for drainage outflow rates and water table...

Evaluation of the reproducibility of lung motion probability distribution function (PDF) using dynamic MRI.

PubMed

Cai, Jing; Read, Paul W; Altes, Talissa A; Molloy, Janelle A; Brookeman, James R; Sheng, Ke

2007-01-21

Treatment planning based on probability distribution function (PDF) of patient geometries has been shown a potential off-line strategy to incorporate organ motion, but the application of such approach highly depends upon the reproducibility of the PDF. In this paper, we investigated the dependences of the PDF reproducibility on the imaging acquisition parameters, specifically the scan time and the frame rate. Three healthy subjects underwent a continuous 5 min magnetic resonance (MR) scan in the sagittal plane with a frame rate of approximately 10 f s-1, and the experiments were repeated with an interval of 2 to 3 weeks. A total of nine pulmonary vessels from different lung regions (upper, middle and lower) were tracked and the dependences of their displacement PDF reproducibility were evaluated as a function of scan time and frame rate. As results, the PDF reproducibility error decreased with prolonged scans and appeared to approach equilibrium state in subjects 2 and 3 within the 5 min scan. The PDF accuracy increased in the power function with the increase of frame rate; however, the PDF reproducibility showed less sensitivity to frame rate presumably due to the randomness of breathing which dominates the effects. As the key component of the PDF-based treatment planning, the reproducibility of the PDF affects the dosimetric accuracy substantially. This study provides a reference for acquiring MR-based PDF of structures in the lung.

Ammonia Offgassing from SA9T

NASA Technical Reports Server (NTRS)

Monje, Oscar; Nolek, Sara D.; Wheeler, Raymond M.

2011-01-01

NH3 is a degradation product of SA9T, a solid-amine sorbent developed by Hamilton Sundstrand, that is continually emitted into the gas stream being conditioned by this sorbent. NH3 offgassing rates were measured using FTIR spectroscopy using a packed bed at similar contact times as offgassing tests conducted at Hamilton Sundstrand and at the Ames Research Center. The bed was challenged with moist air at several flow rates and humidities and NH3 concentration of the effluent was measured for several hours. The NH3 offgassing rates in open-loop testing were calculated from the steady state outlet NH3 concentration and flow rate. NH3 offgassing rates from SA9T were found to be influenced by the contact time with the adsorbent (flow rate) and by the humidity of the inlet gas stream, which are consistent with previous studies. Closed-loop vacuum-swing adsorption cycling rates verified that NH3 offgassing continues when a constant source of water vapor is present.

Continuous aryl alcohol oxidase production under growth-limited conditions using a trickle bed reactor.

PubMed

Pardo-Planas, Oscar; Atiyeh, Hasan K; Prade, Rolf A; Müller, Michael; Wilkins, Mark R

2018-05-01

An A. nidulans strain with a pyridoxine marker was used for continuous production of aryl alcohol oxidase (AAO) in a trickle bed reactor (TBR). Modified medium with reduced zinc, no copper, and 5 g/L ascorbic acid that reduced melanin production and increased AAO productivity under growth limited conditions was used. Two air flow rates, 0.11 L/min (0.1 vvm) and 1.1 L/min (1.0 vvm) were tested. More melanin formation and reduced protein productivity were observed with air flow rate of 1.1 L/min. Three random packings were used as support for the fungus inside the TBR column, two of which were hydrophobic and one which was hydrophilic, and three different dilution rates were tested. The use of GEA BCN 030 hydrophobic packing resulted in greater AAO yield and productivity than the other packings. Increasing dilution rates favored melanin formation and citric, lactic and succinic acid accumulation, which decreased AAO yield and productivity. Copyright © 2018 Elsevier Ltd. All rights reserved.

Biodegradation of the surfactant linear alkylbenzenesulfonate in sewage- contaminated groundwater: A comparison of column experiments and field tracer tests

USGS Publications Warehouse

Krueger, C.J.; Radakovich, K.M.; Sawyer, T.E.; Barber, L.B.; Smith, R.L.; Field, J.A.

1998-01-01

Transport and biodegradation of linear alkylbenzenesulfonate (LAS) in sewage-contaminated groundwater were investigated for a range of dissolved oxygen concentrations. Both laboratory column and an 80-day continuous injection tracer test field experiments were conducted. The rates of LAS biodegradation increased with increasing dissolved oxygen concentrations and indicated the preferential biodegradation of the longer alkyl chain LAS homologues (i.e., C12 and C13) and external isomers (i.e., 2-and 3- phenyl). However, for similar dissolved oxygen concentrations, mass removal rates for LAS generally were 2-3 times greater in laboratory column experiments than in the field tracer test. Under low oxygen conditions (<1 mg/L) only a fraction of the LAS mixture biodegraded in both laboratory and field experiments. Biodegradation rate constants for the continuous injection field test (0.002-0.08 day-1) were comparable to those estimated for a 3-h injection (pulsed) tracer test conducted under similar biogeochemical conditions, indicating that increasing the exposure time of aquifer sediments to LAS did not increase biodegradation rates.Transport and biodegradation of linear alkylbenzenesulfonate (LAS) in sewage-contaminated groundwater were investigated for a range of dissolved oxygen concentrations. Both laboratory column and an 80-day continuous injection tracer test field experiments were conducted. The rates of LAS biodegradation increased with increasing dissolved oxygen concentrations and indicated the preferential biodegradation of the longer alkyl chain LAS homologues (i.e., C12 and C13) and external isomers (i.e., 2- and 3-phenyl). However, for similar dissolved oxygen concentrations, mass removal rates for LAS generally were 2-3 times greater in laboratory column experiments than in the field tracer test. Under low oxygen conditions (<1 mg/L) only a fraction of the LAS mixture biodegraded in both laboratory and field experiments. Biodegradation rate constants for the continuous injection field test (0.002-0.08 day-1) were comparable to those estimated for a 3-h injection (pulsed) tracer test conducted under similar biogeochemical conditions, indicating that increasing the exposure time of aquifer sediments to LAS did not increase biodegradation rates.

Outcome of 100 pregnancies initiated under treatment with cabergoline in hyperprolactinaemic women.

PubMed

Lebbe, Marie; Hubinont, Corinne; Bernard, Pierre; Maiter, Dominique

2010-08-01

Data concerning the safety for pregnancy of cabergoline treatment in hyperprolactinaemic women are still scarce. To exclude a higher than normal risk for miscarriage and congenital malformation in pregnancies initiated under cabergoline treatment. A retrospective study of 100 pregnancies in 72 hyperprolactinaemic women treated with cabergoline at the time of conception and follow-up of the 88 newborn children. Cabergoline was interrupted in 99 pregnancies and continued in one case. Foetal exposure dose to cabergoline was calculated for each pregnancy. Complications of pregnancy and neonatal status were compared to those observed in an age-and delivery time-matched control group of 163 women. The mean foetal exposure dose to cabergoline was 3.6 +/- 4.7 mg. The rate of spontaneous miscarriages was 10%. Three medical terminations of pregnancy were performed for a foetal malformation (3%). Minor to moderate complications were observed in 31% of the pregnancies, a figure similar to that found in the control group. An increase in tumour size (2-8 mm) was observed in 17/37 evaluated cases, needing reintroduction of cabergoline during pregnancy in five patients. The 84 deliveries resulted in 88 infants, three of them presenting with a malformation (3.4%). Neonatal status was comparable to the control group, where a malformation rate of 6.3% was observed. Postnatal development of the children was normal. Cabergoline treatment at the time of conception appears to be safe for both the pregnancy and the neonate, although more data are still needed on a larger number of pregnancies.

Short- and long-term thermo-erosion of ice-rich permafrost coasts in the Laptev Sea region

NASA Astrophysics Data System (ADS)

Günther, F.; Overduin, P. P.; Sandakov, A. V.; Grosse, G.; Grigoriev, M. N.

2013-06-01

Permafrost coasts in the Arctic are susceptible to a variety of changing environmental factors all of which currently point to increasing coastal erosion rates and mass fluxes of sediment and carbon to the shallow arctic shelf seas. Rapid erosion along high yedoma coasts composed of Ice Complex permafrost deposits creates impressive coastal ice cliffs and inspired research for designing and implementing change detection studies for a long time, but continuous quantitative monitoring and a qualitative inventory of coastal thermo-erosion for large coastline segments is still lacking. Our goal is to use observations of thermo-erosion along the mainland coast of the Laptev Sea, in eastern Siberia, to understand how it depends on coastal geomorphology and the relative contributions of water level and atmospheric drivers. We compared multi-temporal sets of orthorectified satellite imagery from 1965 to 2011 for three segments of coastline ranging in length from 73 to 95 km and analyzed thermo-denudation (TD) along the cliff top and thermo-abrasion (TA) along the cliff bottom for two nested time periods: long-term rates (the past 39-43 yr) and short-term rates (the past 1-4 yr). The Normalized Difference Thermo-erosion Index (NDTI) was used as a proxy to qualitatively describe the relative proportions of TD and TA. Mean annual erosion rates at all three sites were higher in recent years (-5.3 ± 1.3 m a-1) than over the long-term mean (-2.2 ± 0.1 m a-1). The Mamontov Klyk coast exhibits primarily spatial variations of thermo-erosion, while intrasite-specific variations caused by local relief were strongest at the Buor Khaya coast, where the slowest long-term rates of around -0.5 ± 0.1 m a-1 were observed. The Oyogos Yar coast showed continuously rapid erosion up to -6.5 ± 0.2 m a-1. In general, variable characteristics of coastal thermo-erosion were observed not only between study sites and over time, but also within single coastal transects along the cliff profile. Varying intensities of cliff bottom and top erosion are leading to diverse qualities of coastal erosion that have different impacts on coastal mass fluxes. The different extents of Ice Complex permafrost degradation within our study sites turned out to influence not only the degree of coupling between TD and TA, and the magnitude of effectively eroded volumes, but also the quantity of organic carbon released to the shallow Laptev Sea from coastal erosion, which ranged on a long-term from 88 ± 21 to 800 ± 61 t per km coastline per year and will correspond to considerably higher amounts, if recently observed more rapid coastal erosion rates prove to be persistent.

Quality-improvement analytics for intravenous infusion pumps.

PubMed

Skledar, Susan J; Niccolai, Cynthia S; Schilling, Dennis; Costello, Susan; Mininni, Nicolette; Ervin, Kelly; Urban, Alana

2013-04-15

The implementation of a smart-pump continuous quality-improvement (CQI) program across a large health system is described, with an emphasis on key metrics for outcomes analyses and program refinement. Three years ago, the University of Pittsburgh Medical Center health system launched a CQI initiative to help ensure the safe use of 6000 smart pumps in its 14 inpatient facilities. A centralized team led by pharmacists is responsible for the retrieval and interpretation of smart-pump data, which is continuously transmitted to a main server. CQI findings are regularly posted on the health system's interdisciplinary intranet. Monitored metrics include rates of compliance with preprogrammed infusion limits, the top 20 drugs involved in alerts, drugs associated with alert-override rates of ≥90%, numbers of alerts by infusion type, nurse responses to alerts, and alert rate per drug library update. Based on the collected CQI data and site-specific requests, four systemwide updates of the smart-pump drug library were performed during the first 18 months of the program, reducing "nuisance alerts" by about 10% per update cycle and enabling targeted interventions to reduce rapid-infusion errors, other adverse drug events (ADEs), and pump-programming workarounds. Over one 12-month period, bedside alerts prompted nurses to reprogram or cancel continuous infusions an average of 400 times per month, potentially averting i.v. medication ADEs. A smart-pump CQI program is an effective tool for enhancing the safety of i.v. medication administration. The ongoing refinement of the drug library through the development and implementation of key interventions promotes the growth and sustainability of the smart-pump initiative systemwide.

["Getting to zero infections" in hemodialysis].

PubMed

Leonardi, Gianluca; Finotto, Giuseppe; Talaia, Marinella; Nappo, Angelo; Dolla, Caterina; Di Vico, Maria Cristina; Diena, Davide; Linsalata, Antonio; Guarena, Cesare; Barbaro, Silvana; Biancone, Luigi

2015-01-01

We describe two measures adopted in hemodialysis outpatient population in order to reduce Central Venous Catheter (CVC) related infections. The first is a nurse staff training in the field project and the second deals with the employment of chlorhexidine-impregnated dressing devices. These actions were performed after high infection rates were observed through a dedicated register. In the limited assistance dialysis center, direct observation (12/2012-02/2013) quantified the gap between the observed and expected health care behaviour. Training needs were defined and a 40 hours nurse staff training in the field was performed on two occasions. In the hospital dialysis center, we introduced alcoholic 2% chlorhexidine solution and chlorhexidine-impregnated dressing devices to the exit site (CHG-Tegaderm and BioPatch). Infections (cumulatively bacteremia/sepsis/skin exit/subcutaneous tunnel) were monitored continuously. Infection rates at the two locations were progressively reduced, reaching a value of zero at the limited assistance center. Nurse staff training in the field produced: two patient reports and three CVC management protocols, Italian language translation of the "The 5 moments of dialysis" WHO poster, alcoholic 2% chlorhexidine adoption to exit-site medication and improvement of environment cleaning/sanitation actions. Our experience shows that continuously monitoring infection rates represents the first step for timely corrective action. The continuous updating of health personnel, codified prevention measures and an ongoing commitment to raise awareness in a routine practice, allows us to obtain the goal of "getting to zero infections". The staff training produced equal or superior results compared to the isolated use of new chlorhexidine-impregnated dressing devices.

Hypoglycemia prediction with subject-specific recursive time-series models.

PubMed

Eren-Oruklu, Meriyan; Cinar, Ali; Quinn, Lauretta

2010-01-01

Avoiding hypoglycemia while keeping glucose within the narrow normoglycemic range (70-120 mg/dl) is a major challenge for patients with type 1 diabetes. Continuous glucose monitors can provide hypoglycemic alarms when the measured glucose decreases below a threshold. However, a better approach is to provide an early alarm that predicts a hypoglycemic episode before it occurs, allowing enough time for the patient to take the necessary precaution to avoid hypoglycemia. We have previously proposed subject-specific recursive models for the prediction of future glucose concentrations and evaluated their prediction performance. In this work, our objective was to evaluate this algorithm further to predict hypoglycemia and provide early hypoglycemic alarms. Three different methods were proposed for alarm decision, where (A) absolute predicted glucose values, (B) cumulative-sum (CUSUM) control chart, and (C) exponentially weighted moving-average (EWMA) control chart were used. Each method was validated using data from the Diabetes Research in Children Network, which consist of measurements from a continuous glucose sensor during an insulin-induced hypoglycemia. Reference serum glucose measurements were used to determine the sensitivity to predict hypoglycemia and the false alarm rate. With the hypoglycemic threshold set to 60 mg/dl, sensitivity of 89, 87.5, and 89% and specificity of 67, 74, and 78% were reported for methods A, B, and C, respectively. Mean values for time to detection were 30 +/- 5.51 (A), 25.8 +/- 6.46 (B), and 27.7 +/- 5.32 (C) minutes. Compared to the absolute value method, both CUSUM and EWMA methods behaved more conservatively before raising an alarm (reduced time to detection), which significantly decreased the false alarm rate and increased the specificity. 2010 Diabetes Technology Society.

Noncontact Infrared-Mediated Heat Transfer During Continuous Freeze-Drying of Unit Doses.

PubMed

Van Bockstal, Pieter-Jan; De Meyer, Laurens; Corver, Jos; Vervaet, Chris; De Beer, Thomas

2017-01-01

Recently, an innovative continuous freeze-drying concept for unit doses was proposed, based on spinning the vials during freezing. An efficient heat transfer during drying is essential to continuously process these spin frozen vials. Therefore, the applicability of noncontact infrared (IR) radiation was examined. The impact of several process and formulation variables on the mass of sublimed ice after 15 min of primary drying (i.e., sublimation rate) and the total drying time was examined. Two experimental designs were performed in which electrical power to the IR heaters, distance between the IR heaters and the spin frozen vial, chamber pressure, product layer thickness, and 5 model formulations were included as factors. A near-infrared spectroscopy method was developed to determine the end point of primary and secondary drying. The sublimation rate was mainly influenced by the electrical power to the IR heaters and the distance between the IR heaters and the vial. The layer thickness had the largest effect on total drying time. The chamber pressure and the 5 model formulations had no significant impact on sublimation rate and total drying time, respectively. This study shows that IR radiation is suitable to provide the energy during the continuous processing of spin frozen vials. Copyright © 2016 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

Recent Subsidence and Erosion at Diverse Wetland Sites in the Southeastern Mississippi Delta Plain

USGS Publications Warehouse

Morton, Robert A.; Bernier, Julie C.; Kelso, Kyle W.

2009-01-01

A prior study (U.S. Geological Survey Open-File Report 2005-1216) examined historical land- and water-area changes and estimated magnitudes of land subsidence and erosion at five wetland sites in the Terrebonne hydrologic basin of the Mississippi delta plain. The present study extends that work by analyzing interior wetland loss and relative magnitudes of subsidence and erosion at five additional wetland sites in the adjacent Barataria hydrologic basin. The Barataria basin sites were selected for their diverse physical settings and their recent (post-1978) conversion from marsh to open water. Historical aerial photography, datum-corrected marsh elevations and water depths, sediment cores, and radiocarbon dates were integrated to evaluate land-water changes in the Mississippi delta plain on both historical and geological time scales. The thickness of the organic-rich sediments (peat) and the elevation of the stratigraphic contact between peat and underlying mud were compared at marsh and open-water sites across areas of formerly continuous marsh to estimate magnitudes of recent delta-plain elevation loss caused by vertical erosion and subsidence of the wetlands. Results of these analyses indicate that erosion exceeded subsidence at most of the study areas, although both processes have contributed to historical wetland loss. Comparison of these results with prior studies indicates that subsidence largely caused rapid interior wetland loss in the Terrebonne basin before 1978, whereas erosional processes primarily caused more gradual interior wetland loss in the Barataria basin after 1978. Decadal variations in rates of relative sea-level rise at a National Ocean Service tide gage, elevation changes between repeat benchmark-leveling surveys, and GPS height monitoring at three National Geodetic Survey Continuously Operating Reference Stations indicate that subsidence rates since the early 1990s are substantially lower than those previously reported and are similar in magnitude to time-averaged subsidence rates at geological time scales. The historical decrease in land-loss rates across the Mississippi delta plain generally is consistent with the recent decrease in subsidence rates within the same region.

A Comparison of Three Commercial Online Vendors.

ERIC Educational Resources Information Center

Hoover, Ryan E.

1979-01-01

Compares database update currency, number of hits, elapsed time, number of offline prints or online types, offline print turnaround time, vendor rates, total search cost, and discounted search cost based on vendor discount rates for five simple searches run on three major commercial vendors' online systems. (CWM)

Correlates of oral contraception continuation.

PubMed

Ewer, P A; Gibbs, J O

1971-05-01

A sample of 139 predominantly black, young, low-income patients who had accepted oral contraception at a publicly supported family planning clinic has been analyzed for correlates of oral contraception continuation. Interviews were conducted 10-12 months after the clinic visit; at this time 38% of the patients continued taking oral contraceptives. It was found that patients with the highest continuation rates were 18-24 years old, in the 2-3 parity group, living with their husbands, had low-parity mothers, and were able to fill prescriptions in less time with more convenient methods of transportation. Discontinuers tended to have high-parity mothers, live with parents or head their own households, and to be in the 13-17 or 25-45 year old age groups. Fear of long-term use of oral contraceptives and perceived side effects appeared to be implicated in discontinuation. The rate of discontinuation may be associated with irregular coital experience and less consistent exposure to pregnancy.

Continuous spin detonation of poorly detonable fuel-air mixtures in annular combustors

NASA Astrophysics Data System (ADS)

Bykovskii, F. A.; Zhdan, S. A.

2017-09-01

This paper reports on the results of experimental investigations of continuous spin detonation of three fuel-air mixtures (syngas-air, CH4/H2-air, and kerosene/H2-air in a flow-type annular cylindrical combustor 503 mm in diameter. The limits of existence of continuous detonation in terms of the specific flow rates of the mixtures (minimum values) are determined. It is found that all gas mixtures, including the least detonable methane-air mixture, with addition of hydrogen can be burned in the continuous spin detonation regime.

Cardiac transplantation in South Carolina: 300 transplants.

PubMed

Crumbley, A J; Odom, Sylvia; Van Bakel, Adrian B; Pereira, Naveen; Ikonomidis, John S; Bradley, Scott; Kratz, John M; Sade, Robert M; Uber, Walt; Stroud, Martha R; Crawford, Fred A

2006-02-01

For nearly 20 years, the Medical University's Heart Transplant Program has been providing the citizens of South Carolina with excellent results with a minimum of delay. We present here the results of our first 300 heart transplants, spanning the first 18 years of the Cardiac Transplant Program at the Medical University. Overall survival has been very good, with one, five and ten year survival rates in the adults being 92 +/- 2%, 78 +/- 3%, and 58 +/- 4%. The children's group showed survival rates of 94 +/- 5%, 79 +/- 11%, and 79 +/- 11% over the same lengths of time. Most recently, the federally sponsored Scientific Registry of Transplant Recipients (www.ustransplant.org, July 2005) reports for MUSC a one-year survival of 97.67% and three-year survival of 90.74%; both leading the Southeast. We attribute this success to the dedicated work of health care workers at all levels who believe in attention to detail and that the patient always comes first. It is our hope that we will be able to continue to provide expert, state-of-the-art, cardiac transplant services long into the future, while continuing to expand our heart failure management program as dictated by further developments in this rapidly evolving specialty.

Fabrication of co-continuous poly(ε-caprolactone)/polyglycolide blend scaffolds for tissue engineering

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

Allaf, Rula M.; Rivero, Iris V.; Ivanov, Ilia N.

2015-06-06

The apparent inability of a single biomaterial to meet all the requirements for tissue engineering scaffolds has led to continual research in novel engineered biomaterials. One method to provide new materials and fine-tune their properties is via mixing materials. Here in this study, a biodegradable powder blend of poly(ε-caprolactone) (PCL), polyglycolide (PGA), and poly(ethylene oxide) (PEO) was prepared and three-dimensional interconnected porous PCL/PGA scaffolds were fabricated by combining cryomilling and compression molding/polymer leaching techniques. The resultant porous scaffolds exhibited co-continuous morphologies with ~50% porosity. Mean pore sizes of 24 and 56 μm were achieved by varying milling time. The scaffoldsmore » displayed high mechanical properties and water uptake, in addition to a remarkably fast degradation rate. The results demonstrate the potential of this fabrication approach to obtain PCL/PGA blend scaffolds with interconnected porosity. In general, these results provide significant insight into an approach that will lead to the development of new composites and blends in scaffold manufacturing.« less

Three-dimensional optical coherence tomography of the embryonic murine cardiovascular system

NASA Astrophysics Data System (ADS)

Luo, Wei; Marks, Daniel L.; Ralston, Tyler S.; Boppart, Stephen A.

2006-03-01

Optical coherence tomography (OCT) is an emerging high-resolution real-time biomedical imaging technology that has potential as a novel investigational tool in developmental biology and functional genomics. In this study, murine embryos and embryonic hearts are visualized with an OCT system capable of 2-µm axial and 15-µm lateral resolution and with real-time acquisition rates. We present, to our knowledge, the first sets of high-resolution 2- and 3-D OCT images that reveal the internal structures of the mammalian (murine) embryo (E10.5) and embryonic (E14.5 and E17.5) cardiovascular system. Strong correlations are observed between OCT images and corresponding hematoxylin- and eosin-stained histological sections. Real-time in vivo embryonic (E10.5) heart activity is captured by spectral-domain optical coherence tomography, processed, and displayed at a continuous rate of five frames per second. With the ability to obtain not only high-resolution anatomical data but also functional information during cardiovascular development, the OCT technology has the potential to visualize and quantify changes in murine development and in congenital and induced heart disease, as well as enable a wide range of basic in vitro and in vivo research studies in functional genomics.

An automated SO2 camera system for continuous, real-time monitoring of gas emissions from Kīlauea Volcano's summit Overlook Crater

USGS Publications Warehouse

Kern, Christoph; Sutton, Jeff; Elias, Tamar; Lee, Robert Lopaka; Kamibayashi, Kevan P.; Antolik, Loren; Werner, Cynthia A.

2015-01-01

SO2 camera systems allow rapid two-dimensional imaging of sulfur dioxide (SO2) emitted from volcanic vents. Here, we describe the development of an SO2 camera system specifically designed for semi-permanent field installation and continuous use. The integration of innovative but largely “off-the-shelf” components allowed us to assemble a robust and highly customizable instrument capable of continuous, long-term deployment at Kīlauea Volcano's summit Overlook Crater. Recorded imagery is telemetered to the USGS Hawaiian Volcano Observatory (HVO) where a novel automatic retrieval algorithm derives SO2 column densities and emission rates in real-time. Imagery and corresponding emission rates displayed in the HVO operations center and on the internal observatory website provide HVO staff with useful information for assessing the volcano's current activity. The ever-growing archive of continuous imagery and high-resolution emission rates in combination with continuous data from other monitoring techniques provides insight into shallow volcanic processes occurring at the Overlook Crater. An exemplary dataset from September 2013 is discussed in which a variation in the efficiency of shallow circulation and convection, the processes that transport volatile-rich magma to the surface of the summit lava lake, appears to have caused two distinctly different phases of lake activity and degassing. This first successful deployment of an SO2 camera for continuous, real-time volcano monitoring shows how this versatile technique might soon be adapted and applied to monitor SO2 degassing at other volcanoes around the world.

An automated SO2 camera system for continuous, real-time monitoring of gas emissions from Kīlauea Volcano's summit Overlook Crater

NASA Astrophysics Data System (ADS)

Kern, Christoph; Sutton, Jeff; Elias, Tamar; Lee, Lopaka; Kamibayashi, Kevan; Antolik, Loren; Werner, Cynthia

2015-07-01

SO2 camera systems allow rapid two-dimensional imaging of sulfur dioxide (SO2) emitted from volcanic vents. Here, we describe the development of an SO2 camera system specifically designed for semi-permanent field installation and continuous use. The integration of innovative but largely ;off-the-shelf; components allowed us to assemble a robust and highly customizable instrument capable of continuous, long-term deployment at Kīlauea Volcano's summit Overlook Crater. Recorded imagery is telemetered to the USGS Hawaiian Volcano Observatory (HVO) where a novel automatic retrieval algorithm derives SO2 column densities and emission rates in real-time. Imagery and corresponding emission rates displayed in the HVO operations center and on the internal observatory website provide HVO staff with useful information for assessing the volcano's current activity. The ever-growing archive of continuous imagery and high-resolution emission rates in combination with continuous data from other monitoring techniques provides insight into shallow volcanic processes occurring at the Overlook Crater. An exemplary dataset from September 2013 is discussed in which a variation in the efficiency of shallow circulation and convection, the processes that transport volatile-rich magma to the surface of the summit lava lake, appears to have caused two distinctly different phases of lake activity and degassing. This first successful deployment of an SO2 camera for continuous, real-time volcano monitoring shows how this versatile technique might soon be adapted and applied to monitor SO2 degassing at other volcanoes around the world.

Simulated effects of ground-water management scenarios on the Santa Fe group aquifer system, Middle Rio Grande Basin, New Mexico, 2001-40

USGS Publications Warehouse

Bexfield, Laura M.; McAda, Douglas P.

2003-01-01

Future conditions in the Santa Fe Group aquifer system through 2040 were simulated using the most recent revision of the U.S. Geological Survey groundwater- flow model for the Middle Rio Grande Basin. Three simulations were performed to investigate the likely effects of different scenarios of future groundwater pumping by the City of Albuquerque on the ground-water system. For simulation I, pumping was held constant at known year-2000 rates. For simulation II, pumping was increased to simulate the use of pumping to meet all projected city water demand through 2040. For simulation III, pumpingwas reduced in accordance with a plan by the City of Albuquerque to use surfacewater to meet most of the projectedwater demand. The simulations indicate that for each of the three pumping scenarios, substantial additional watertable declines would occur in some areas of the basin through 2040. However, the reduced pumping scenario of simulation III also results in water-table rise over a broad area of the city. All three scenarios indicate that the contributions of aquifer storage and river leakage to the ground-water system would change between 2000 and 2040. Comparisons among the results for simulations I, II, and III indicate that the various pumping scenarios have substantially different effects on water-level declines in the Albuquerque area and on the contribution of each water-budget component to the total budget for the ground-water system. Between 2000 and 2040, water-level declines for continued pumping at year-2000 rates are as much as 120 feet greater than for reduced pumping; water-level declines for increased pumping to meet all projected city demand are as much as 160 feet greater. Over the same time period, reduced pumping results in retention in aquifer storage of about 1,536,000 acre-feet of ground water as compared with continued pumping at year- 2000 rates and of about 2,257,000 acre-feet as compared with increased pumping. The quantity of water retained in the Rio Grande as a result of reduced pumping and the associated decrease in induced recharge from the river is about 731,000 acre-feet as compared with continued pumping at year-2000 rates and about 872,000 acre-feet as compared with increased pumping. Reduced pumping results in slight increases in the quantity of water lost from the groundwater system to evapotranspiration and agriculturaldrain flow compared with the other pumping scenarios.

Use of granulocyte-colony stimulating factor to prevent recurrent clozapine-induced neutropenia on drug rechallenge: A systematic review of the literature and clinical recommendations.

PubMed

Myles, Nicholas; Myles, Hannah; Clark, Scott R; Bird, Robert; Siskind, Dan

2017-10-01

Clozapine is the most effective medication for treatment-refractory schizophrenia; however, its use is contraindicated in people who have had previous clozapine-induced neutropenia. Co-prescription of granulocyte-colony stimulating factor may prevent recurrent neutropenia and allow continuation or rechallenge of clozapine. Systematic review of literature reporting the use of granulocyte-colony stimulating factor to allow rechallenge or continuation of clozapine in people with previous episodes of clozapine-induced neutropenia. The efficacy of granulocyte-colony stimulating factor and predictors of successful rechallenge will be determined to elucidate whether evidence-based recommendations can be made regarding the use of granulocyte-colony stimulating factor in this context. A total of 17 articles were identified that reported on clozapine rechallenge with granulocyte-colony stimulating factor support. In all, 76% of cases were able to continue clozapine at median follow-up of 12 months. There were no clear clinical or laboratory predictors of successful rechallenge; however, initial neutropenia was more severe in successful cases compared to unsuccessful cases. Cases co-prescribed lithium had lower success rates of rechallenge (60%) compared to those who were not prescribed lithium (81%). The most commonly reported rechallenge strategy was use of filgrastim 150-480 µg between daily to three times a week. There were no medication-specific side effects of granulocyte-colony stimulating factor reported apart from euphoria in one case. Three cases who failed granulocyte-colony stimulating factor had bacterial infection at time of recurrent neutropenia. No deaths were reported. Preliminary data suggest granulocyte-colony stimulating factor is safe and effective in facilitating rechallenge with clozapine. Clinical recommendations for use are discussed.

GPs asking patients to self-rate their health: a qualitative study

PubMed Central

Waller, Göran; Hamberg, Katarina; Forssén, Annika

2015-01-01

Background In epidemiological research, self-rated health is an independent predictor of mortality, cardiovascular diseases, and other critical outcomes. It is recommended for clinical use, but research is lacking. Aim To investigate what happens in consultations when the question ‘How would you assess your general health compared with others your own age?’ is posed. Design and setting Authentic consultations with GPs at health centres in Sweden. Method Thirty-three planned visits concerning diabetes, pain, or undiagnosed symptoms were voice-recorded. Dialogue regarding self-rated health was transcribed verbatim and analysed using a systematic text condensation method. Speaking time of patients and doctors was measured and the doctors’ assessment of the value of the question was documented in a short questionnaire. Results Two overarching themes are used to describe patients’ responses to the question. First, there was an immediate reaction, often expressing strong emotions, setting the tone of the dialogue and influencing the continued conversation. This was followed by reflection regarding their functional ability, management of illnesses and risks, and/or situation in life. The GPs maintained an attitude of active listening. They sometimes reported a slight increase in consultation time or feeling disturbed by the question, but mostly judged it as valuable, shedding additional light on the patients’ situation and making it easier to discuss difficulties and resources. The patients’ speaking time increased noticeably during this part of the consultation. Conclusion Asking patients to comparatively self-rate their health is an effective tool in general practice. PMID:26324500

Continued Rapid Uplift at Laguna del Maule Volcanic Field (Chile) from 2007 through 2014

NASA Astrophysics Data System (ADS)

Le Mével, H.; Feigl, K. L.; Cordova, L.; DeMets, C.; Lundgren, P.

2014-12-01

The current rate of uplift at Laguna del Maule (LdM) volcanic field in Chile is among the highest ever observed geodetically for a volcano that is not actively erupting. Using data from interferometric synthetic aperture radar (InSAR) and the Global Positioning System (GPS) recorded at five continuously operating stations, we measure the deformation field with dense sampling in time (1/day) and space (1/hectare). These data track the temporal evolution of the current unrest episode from its inception (sometime between 2004 and 2007) to vertical velocities faster than 200 mm/yr that continue through (at least) July 2014. Building on our previous work, we evaluate the temporal evolution by analyzing data from InSAR (ALOS, TerraSAR-X, TanDEM-X) and GPS [http://dx.doi.org/ 10.1093/gji/ggt438]. In addition, we consider InSAR data from (ERS, ENVISAT, COSMO-Skymed, and UAVSAR), as well as constraints from magneto-telluric (MT), seismic, and gravity surveys. The goal is to test the hypothesis that a recent magma intrusion is feeding a large, existing magma reservoir. What will happen next? To address this question, we analyze the temporal evolution of deformation at other large silicic systems such as Yellowstone, Long Valley, and Three Sisters, during well-studied episodes of unrest. We consider several parameterizations, including piecewise linear, parabolic, and Gaussian functions of time. By choosing the best-fitting model, we expect to constrain the time scales of such episodes and elucidate the processes driving them.

[The endpoint detection of cough signal in continuous speech].

PubMed

Yang, Guoqing; Mo, Hongqiang; Li, Wen; Lian, Lianfang; Zheng, Zeguang

2010-06-01

The endpoint detection of cough signal in continuous speech has been researched in order to improve the efficiency and veracity of manual recognition or computer-based automatic recognition. First, using the short time zero crossing ratio(ZCR) for identifying the suspicious coughs and getting the threshold of short time energy based on acoustic characteristics of cough. Then, the short time energy is combined with short time ZCR in order to implement the endpoint detection of cough in continuous speech. To evaluate the effect of the method, first, the virtual number of coughs in each recording was identified by two experienced doctors using the graphical user interface (GUI). Second, the recordings were analyzed by automatic endpoint detection program under Matlab7.0. Finally, the comparison between these two results showed: The error rate of undetected cough is 2.18%, and 98.13% of noise, silence and speech were removed. The way of setting short time energy threshold is robust. The endpoint detection program can remove most speech and noise, thus maintaining a lower rate of error.

Healthcare Utilization After a Children's Health Insurance Program Expansion in Oregon.

PubMed

Bailey, Steffani R; Marino, Miguel; Hoopes, Megan; Heintzman, John; Gold, Rachel; Angier, Heather; O'Malley, Jean P; DeVoe, Jennifer E

2016-05-01

The future of the Children's Health Insurance Program (CHIP) is uncertain after 2017. Survey-based research shows positive associations between CHIP expansions and children's healthcare utilization. To build on this prior work, we used electronic health record (EHR) data to assess temporal patterns of healthcare utilization after Oregon's 2009-2010 CHIP expansion. We hypothesized increased post-expansion utilization among children who gained public insurance. Using EHR data from 154 Oregon community health centers, we conducted a retrospective cohort study of pediatric patients (2-18 years old) who gained public insurance coverage during the Oregon expansion (n = 3054), compared to those who were continuously publicly insured (n = 10,946) or continuously uninsured (n = 10,307) during the 2-year study period. We compared pre-post rates of primary care visits, well-child visits, and dental visits within- and between-groups. We also conducted longitudinal analysis of monthly visit rates, comparing the three insurance groups. After Oregon's 2009-2010 CHIP expansions, newly insured patients' utilization rates were more than double their pre-expansion rates [adjusted rate ratios (95 % confidence intervals); increases ranged from 2.10 (1.94-2.26) for primary care visits to 2.77 (2.56-2.99) for dental visits]. Utilization among the newly insured spiked shortly after coverage began, then leveled off, but remained higher than the uninsured group. This study used EHR data to confirm that CHIP expansions are associated with increased utilization of essential pediatric primary and preventive care. These findings are timely to pending policy decisions that could impact children's access to public health insurance in the United States.

Quantifying the physical demands of a musical performance and their effects on performance quality.

PubMed

Drinkwater, Eric J; Klopper, Christopher J

2010-06-01

This study investigated the effects of fatigue on performance quality induced by a prolonged musical performance. Ten participants prepared 10 min of repertoire for their chosen wind instrument that they played three times consecutively. Prior to the performance and within short breaks between performances, researchers collected heart rate, respiratory rate, blood pressure, blood lactate concentration, rating of perceived exertion (RPE), and rating of anxiety. All performances were audio recorded and later analysed for performance errors. Reliability in assessing performance errors was assessed by typical error of measure (TEM) of 15 repeat performances. Results indicate all markers of physical stress significantly increased by a moderate to large amount (4.6 to 62.2%; d = 0.50 to 1.54) once the performance began, while heart rate, respirations, and RPE continued to rise by a small to large amount (4.9 to 23.5%; d = 0.28 to 0.93) with each performance. Observed changes in performance between performances were well in excess of the TEM of 7.4%. There was a significant small (21%, d = 0.43) decrease in errors after the first performance; after the second performance, there was a significant large increase (70.4%, d = 1.14). The initial increase in physiological stress with corresponding decrease in errors after the first performance likely indicates "warming up," while the continued increase in markers of physical stress with dramatic decrement in performance quality likely indicates fatigue. Musicians may consider the relevance of physical fitness to maintaining performance quality over the duration of a performance.

Development and testing of a CW-EPR apparatus for imaging of short-lifetime nitroxyl radicals in mouse head

NASA Astrophysics Data System (ADS)

Sato-Akaba, Hideo; Fujii, Hirotada; Hirata, Hiroshi

2008-08-01

This article describes a method for reducing the acquisition time in three-dimensional (3D) continuous-wave electron paramagnetic resonance (CW-EPR) imaging. To visualize nitroxyl spin probes, which have a short lifetime in living organisms, the acquisition time for a data set of spectral projections should be shorter than the lifetime of the spin probes. To decrease the total time required for data acquisition, the duration of magnetic field scanning was reduced to 0.5 s. Moreover, the number of projections was decreased by using the concept of a uniform distribution. To demonstrate this faster data acquisition, two kinds of nitroxyl radicals with different decay rates were measured in mice. 3D EPR imaging of 4-hydroxy-2,2,6,6-tetramethylpiperidine-d 17-1- 15N-1-oxyl in mouse head was successfully carried out. 3D EPR imaging of nitroxyl spin probes with a half-life of a few minutes was achieved for the first time in live animals.

Effects of N and B on continuous cooling transformation diagrams of Mo-V-Ti micro-alloyed steels

NASA Astrophysics Data System (ADS)

Yuhui, Wang; Bo, Liao; Ligang, Liu; Xianfeng, Li; Hang, Su; Caifu, Yang; Qingfeng, Wang

2012-05-01

Effects of the single addition of nitrogen (N) and boron (B) and the combined addition of N and B on continuous cooling transformation (CCT) diagrams and properties of the three Mo-V-Ti micro-alloyed steels were investigated by means of a combined method of dilatometry and metallography. Microstructures observed in continuous cooled specimens were composed of pearlite (P), quasi-polygonal ferrite (QPF), granular bainite (GB), acicular ferrite (AF), lath-like bainite (LB) and martensite (M) depending on the cooling rates and transformation temperatures. Single addition of 12 ppm B effectively reduced the formation of QPF and broadened the cooling rate region for LB and M. Added N makes the action of B invalid and the QPF region was prominently broadened, and even though the cooling rate is higher than 50°C s-1, it cannot obtain full bainite.

Numerical Evaluation of the "Dual-Kernel Counter-flow" Matric Convolution Integral that Arises in Discrete/Continuous (D/C) Control Theory

NASA Technical Reports Server (NTRS)

Nixon, Douglas D.

2009-01-01

Discrete/Continuous (D/C) control theory is a new generalized theory of discrete-time control that expands the concept of conventional (exact) discrete-time control to create a framework for design and implementation of discretetime control systems that include a continuous-time command function generator so that actuator commands need not be constant between control decisions, but can be more generally defined and implemented as functions that vary with time across sample period. Because the plant/control system construct contains two linear subsystems arranged in tandem, a novel dual-kernel counter-flow convolution integral appears in the formulation. As part of the D/C system design and implementation process, numerical evaluation of that integral over the sample period is required. Three fundamentally different evaluation methods and associated algorithms are derived for the constant-coefficient case. Numerical results are matched against three available examples that have closed-form solutions.

Northeastern Florida Bay estuarine creek data, water years 1996-2000

USGS Publications Warehouse

Hittle, Clinton D.; Zucker, Mark A.

2004-01-01

From October 1995 to September 2000 (water years 1996-2000), continuous 15-minute stage, water velocity, salinity, and water temperature data were collected at seven estuarine creeks that flow into northeastern Florida Bay. These creeks include West Highway Creek, Stillwater Creek, Trout Creek, Mud Creek, Taylor River, Upstream Taylor River, and McCormick Creek. Discharge was computed at 15-minute intervals using mean water velocity and the cross-sectional area of the channel. Fifteen-minute unit values are presented for comparison of the quantity, quality, timing, and distribution of flows through the creeks. Revised discharge estimation formulas are presented for three noninstrumented sites (East Highway Creek, Oregon Creek and Stillwater Creek) that utilize an improved West Highway discharge rating. Stillwater Creek and Upstream Taylor River were originally noninstrumented sites; both were fully instrumented in 1999. Discharge rating equations are presented for these sites and were developed using a simple linear regression.

Canonical Structure and Orthogonality of Forces and Currents in Irreversible Markov Chains

NASA Astrophysics Data System (ADS)

Kaiser, Marcus; Jack, Robert L.; Zimmer, Johannes

2018-03-01

We discuss a canonical structure that provides a unifying description of dynamical large deviations for irreversible finite state Markov chains (continuous time), Onsager theory, and Macroscopic Fluctuation Theory (MFT). For Markov chains, this theory involves a non-linear relation between probability currents and their conjugate forces. Within this framework, we show how the forces can be split into two components, which are orthogonal to each other, in a generalised sense. This splitting allows a decomposition of the pathwise rate function into three terms, which have physical interpretations in terms of dissipation and convergence to equilibrium. Similar decompositions hold for rate functions at level 2 and level 2.5. These results clarify how bounds on entropy production and fluctuation theorems emerge from the underlying dynamical rules. We discuss how these results for Markov chains are related to similar structures within MFT, which describes hydrodynamic limits of such microscopic models.

Aethalometer™ Instrument Handbook

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

Sedlacek, Arthur J.

2016-04-01

The Aethalometer is an instrument that provides a real-time readout of the concentration of “Black” or “Elemental” carbon aerosol particles (BC or E) in an air stream (see Figure 1 and Figure 2). It is a self-contained instrument that measures the rate of change of optical transmission through a spot on a filter where aerosol is being continuously collected and uses the information to calculate the concentration of optically absorbing material in the sampled air stream. The instrument measures the transmitted light intensities through the “sensing” portion of the filter, on which the aerosol spot is being collected, and amore » “reference” portion of the filter as a check on the stability of the optical source. A mass flowmeter monitors the sample air flow rate. The data from these three measurements is used to determine the mean BC content of the air stream.« less

Three-dimensional, automated, real-time video system for tracking limb motion in brain-machine interface studies.

PubMed

Peikon, Ian D; Fitzsimmons, Nathan A; Lebedev, Mikhail A; Nicolelis, Miguel A L

2009-06-15

Collection and analysis of limb kinematic data are essential components of the study of biological motion, including research into biomechanics, kinesiology, neurophysiology and brain-machine interfaces (BMIs). In particular, BMI research requires advanced, real-time systems capable of sampling limb kinematics with minimal contact to the subject's body. To answer this demand, we have developed an automated video tracking system for real-time tracking of multiple body parts in freely behaving primates. The system employs high-contrast markers painted on the animal's joints to continuously track the three-dimensional positions of their limbs during activity. Two-dimensional coordinates captured by each video camera are combined and converted to three-dimensional coordinates using a quadratic fitting algorithm. Real-time operation of the system is accomplished using direct memory access (DMA). The system tracks the markers at a rate of 52 frames per second (fps) in real-time and up to 100fps if video recordings are captured to be later analyzed off-line. The system has been tested in several BMI primate experiments, in which limb position was sampled simultaneously with chronic recordings of the extracellular activity of hundreds of cortical cells. During these recordings, multiple computational models were employed to extract a series of kinematic parameters from neuronal ensemble activity in real-time. The system operated reliably under these experimental conditions and was able to compensate for marker occlusions that occurred during natural movements. We propose that this system could also be extended to applications that include other classes of biological motion.

Enzymatic hydrolysis of cellulose dissolved in N-methyl morpholine oxide/water solutions.

PubMed

Ramakrishnan, S; Collier, J; Oyetunji, R; Stutts, B; Burnett, R

2010-07-01

In situ hydrolysis of cellulose (dissolving pulp) in N-methyl morpholine oxide (NMMO) solutions by commercially available Accellerase1000 is carried out. The yield of reducing sugars is followed as a function of time at three different temperatures and four different enzyme loadings to study the effect of system parameters on enzymatic hydrolysis. Initial results show that rates of hydrolysis of cellulose and yields of reducing sugars in the presence of NMMO-water is superior initially (ratio of initial reaction rates approximately 4) and comparable to that of regenerated cellulose (for times greater than 5h) when suspended in aqueous solutions. The usage of Accellerase1000 results predominantly in the formation of glucose with minimal amounts of cellobiose. This study proves the ability of cellulases to remain active in NMMO to carry out an in situ saccharification of cellulose thus eliminating the need to recover regenerated cellulose. Thus this work will form the basis for developing a continuous process for conversion of biomass to hydrogen, ethanol and other hydrocarbons. Copyright 2009 Elsevier Ltd. All rights reserved.

Diurnal variation of eye movement and heart rate variability in the human fetus at term.

PubMed

Morokuma, S; Horimoto, N; Satoh, S; Nakano, H

2001-07-01

To elucidate diurnal variations in eye movement and fetal heart rate (FHR) variability in the term fetus, we observed these two parameters continuously for 24 h, using real-time ultrasound and Doppler cardiotocograph, respectively. Studied were five uncomplicated fetuses at term. The time series data of the presence and absence of eye movement and mean FHR value for each 1 min were analyzed using the maximum entropy method (MEM) and subsequent nonlinear least squares fitting. According to the power value of eye movement, all five cases were classified into two groups: three cases in the large power group and two cases in the small power group. The acrophases of eye movement and FHR variability in the large power group were close, thereby implying the existence of a diurnal rhythm in both these parameters and also that they are synchronized. In the small power group, the acrophases were separated. The synchronization of eye movement and FHR variability in the large power group suggests that these phenomena are governed by a common central mechanism related to diurnal rhythm generation.

Trio Student Support Services: A Comparative Study of African American Students at Three Texas Universities

ERIC Educational Resources Information Center

Powell, Hattie Marie

2013-01-01

Although access to postsecondary education for ethnic minorities has increased since desegregation in 1954, the college completion rates for these groups have not, particularly for African Americans. For this reason, it is important to continue to examine strategies that contribute to increases in completion rates for African Americans. The…

Continuous sweep versus discrete step protocols for studying effects of wearable robot assistance magnitude.

PubMed

Malcolm, Philippe; Rossi, Denise Martineli; Siviy, Christopher; Lee, Sangjun; Quinlivan, Brendan Thomas; Grimmer, Martin; Walsh, Conor J

2017-07-12

Different groups developed wearable robots for walking assistance, but there is still a need for methods to quickly tune actuation parameters for each robot and population or sometimes even for individual users. Protocols where parameters are held constant for multiple minutes have traditionally been used for evaluating responses to parameter changes such as metabolic rate or walking symmetry. However, these discrete protocols are time-consuming. Recently, protocols have been proposed where a parameter is changed in a continuous way. The aim of the present study was to compare effects of continuously varying assistance magnitude with a soft exosuit against discrete step conditions. Seven participants walked on a treadmill wearing a soft exosuit that assists plantarflexion and hip flexion. In Continuous-up, peak exosuit ankle moment linearly increased from approximately 0 to 38% of biological moment over 10 min. Continuous-down was the opposite. In Discrete, participants underwent five periods of 5 min with steady peak moment levels distributed over the same range as Continuous-up and Continuous-down. We calculated metabolic rate for the entire Continuous-up and Continuous-down conditions and the last 2 min of each Discrete force level. We compared kinematics, kinetics and metabolic rate between conditions by curve fitting versus peak moment. Reduction in metabolic rate compared to Powered-off was smaller in Continuous-up than in Continuous-down at most peak moment levels, due to physiological dynamics causing metabolic measurements in Continuous-up and Continuous-down to lag behind the values expected during steady-state testing. When evaluating the average slope of metabolic reduction over the entire peak moment range there was no significant difference between Continuous-down and Discrete. Attempting to correct the lag in metabolics by taking the average of Continuous-up and Continuous-down removed all significant differences versus Discrete. For kinematic and kinetic parameters, there were no differences between all conditions. The finding that there were no differences in biomechanical parameters between all conditions suggests that biomechanical parameters can be recorded with the shortest protocol condition (i.e. single Continuous directions). The shorter time and higher resolution data of continuous sweep protocols hold promise for the future study of human interaction with wearable robots.

The Progenitor Dependence of Core-collapse Supernovae from Three-dimensional Simulations with Progenitor Models of 12–40 M ⊙

NASA Astrophysics Data System (ADS)

Ott, Christian D.; Roberts, Luke F.; da Silva Schneider, André; Fedrow, Joseph M.; Haas, Roland; Schnetter, Erik

2018-03-01

We present a first study of the progenitor star dependence of the three-dimensional (3D) neutrino mechanism of core-collapse supernovae. We employ full 3D general-relativistic multi-group neutrino radiation-hydrodynamics and simulate the postbounce evolutions of progenitors with zero-age main sequence masses of 12, 15, 20, 27, and 40 M ⊙. All progenitors, with the exception of the 12 M ⊙ star, experience shock runaway by the end of their simulations. In most cases, a strongly asymmetric explosion will result. We find three qualitatively distinct evolutions that suggest a complex dependence of explosion dynamics on progenitor density structure, neutrino heating, and 3D flow. (1) Progenitors with massive cores, shallow density profiles, and high post-core-bounce accretion rates experience very strong neutrino heating and neutrino-driven turbulent convection, leading to early shock runaway. Accretion continues at a high rate, likely leading to black hole formation. (2) Intermediate progenitors experience neutrino-driven, turbulence-aided explosions triggered by the arrival of density discontinuities at the shock. These occur typically at the silicon/silicon–oxygen shell boundary. (3) Progenitors with small cores and density profiles without strong discontinuities experience shock recession and develop the 3D standing-accretion shock instability (SASI). Shock runaway ensues late, once declining accretion rate, SASI, and neutrino-driven convection create favorable conditions. These differences in explosion times and dynamics result in a non-monotonic relationship between progenitor and compact remnant mass.

Continuous-time system identification of a smoking cessation intervention

NASA Astrophysics Data System (ADS)

Timms, Kevin P.; Rivera, Daniel E.; Collins, Linda M.; Piper, Megan E.

2014-07-01

Cigarette smoking is a major global public health issue and the leading cause of preventable death in the United States. Toward a goal of designing better smoking cessation treatments, system identification techniques are applied to intervention data to describe smoking cessation as a process of behaviour change. System identification problems that draw from two modelling paradigms in quantitative psychology (statistical mediation and self-regulation) are considered, consisting of a series of continuous-time estimation problems. A continuous-time dynamic modelling approach is employed to describe the response of craving and smoking rates during a quit attempt, as captured in data from a smoking cessation clinical trial. The use of continuous-time models provide benefits of parsimony, ease of interpretation, and the opportunity to work with uneven or missing data.

Meta-analysis of Timing for Microsurgical Free-Flap Reconstruction for Lower Limb Injury: Evaluation of the Godina Principles.

PubMed

Haykal, Siba; Roy, Mélissa; Patel, Ashit

2018-05-01

 In 1986, Marko Godina published his seminal work regarding the timing of free-flap reconstruction for traumatic extremity defects. Early reconstruction, compared with delayed and late reconstruction resulted in significant decreases in free-flap failure rate, post-operative infections, hospitalization time, bone healing time, and number of additional anesthesias. The objective of this manuscript was to evaluate whether these principles continue to apply.  A meta-analysis was performed analyzing articles from Medline, Embase, and Pubmed. Four hundred and ninety-two articles were screened, and 134 articles were assessed for eligibility. Following full-text review, 43 articles were included in this study.  The exact timing for free-flap reconstruction, free-flap failure rate, infection rate, and follow-up was defined in all 43 articles. Early free-flap reconstruction was found to have significantly lower rates of free-flap failure and infection in comparison to delayed reconstruction ( p  = 0.008; p  = 0.0004). Compared with late reconstruction, early reconstruction was found to have significantly lower infection rates only ( p  = 0.01) with no difference in free-flap failures rates. Early reconstruction was found to lead to fewer additional procedures ( p  = 0.03). No statistical significance was found for bone healing time or hospitalization time.  Early free-flap reconstruction performed within the first 72 hours resulted in a decreased rate of free-flap failures, infection, and additional procedures with no difference in other parameters. The largest majority of free flaps continue to be performed in a delayed time frame. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Electrochemical in situ regeneration of granular activated carbon using a three-dimensional reactor.

PubMed

Sun, Hong; Liu, Zhigang; Wang, Ying; Li, Yansheng

2013-12-01

Electrochemical in situ regeneration of granular activated carbon (GAC) saturated with phenol was experimentally investigated using a three-dimensional electrode reactor with titanium filter electrode arrays. The feasibility of the electrochemical regeneration has been assessed by monitoring the regeneration efficiency and chemical oxygen demand (COD). The influence of the applied current, the effluent flow rate, and the effluent path of the electrochemical cell have been systematically studied. Under the optimum conditions, the regeneration efficiency of GAC could reach 94% in 2 hr, and no significant declination was observed after five-time continuous adsorption-regeneration cycles. The adsorption of organic pollutants was almost completely mineralized due to electrochemical oxidation, indicating that this regeneration process is much more potentially cost-effective for application. Copyright © 2013 The Research Centre for Eco-Environmental Sciences, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.

The dynamics of fidelity over the time course of long-term memory.

PubMed

Persaud, Kimele; Hemmer, Pernille

2016-08-01

Bayesian models of cognition assume that prior knowledge about the world influences judgments. Recent approaches have suggested that the loss of fidelity from working to long-term (LT) memory is simply due to an increased rate of guessing (e.g. Brady, Konkle, Gill, Oliva, & Alvarez, 2013). That is, recall is the result of either remembering (with some noise) or guessing. This stands in contrast to Bayesian models of cognition while assume that prior knowledge about the world influences judgments, and that recall is a combination of expectations learned from the environment and noisy memory representations. Here, we evaluate the time course of fidelity in LT episodic memory, and the relative contribution of prior category knowledge and guessing, using a continuous recall paradigm. At an aggregate level, performance reflects a high rate of guessing. However, when aggregate data is partitioned by lag (i.e., the number of presentations from study to test), or is un-aggregated, performance appears to be more complex than just remembering with some noise and guessing. We implemented three models: the standard remember-guess model, a three-component remember-guess model, and a Bayesian mixture model and evaluated these models against the data. The results emphasize the importance of taking into account the influence of prior category knowledge on memory. Copyright © 2016 Elsevier Inc. All rights reserved.

Development of a CFD code for casting simulation

NASA Technical Reports Server (NTRS)

Murph, Jesse E.

1993-01-01

Because of high rejection rates for large structural castings (e.g., the Space Shuttle Main Engine Alternate Turbopump Design Program), a reliable casting simulation computer code is very desirable. This code would reduce both the development time and life cycle costs by allowing accurate modeling of the entire casting process. While this code could be used for other types of castings, the most significant reductions of time and cost would probably be realized in complex investment castings, where any reduction in the number of development castings would be of significant benefit. The casting process is conveniently divided into three distinct phases: (1) mold filling, where the melt is poured or forced into the mold cavity; (2) solidification, where the melt undergoes a phase change to the solid state; and (3) cool down, where the solidified part continues to cool to ambient conditions. While these phases may appear to be separate and distinct, temporal overlaps do exist between phases (e.g., local solidification occurring during mold filling), and some phenomenological events are affected by others (e.g., residual stresses depend on solidification and cooling rates). Therefore, a reliable code must accurately model all three phases and the interactions between each. While many codes have been developed (to various stages of complexity) to model the solidification and cool down phases, only a few codes have been developed to model mold filling.

Schedule-induced drinking: rate of food delivery and Herrnstein's equation.

PubMed Central

Wetherington, C L

1979-01-01

Schedule-induced drinking was measured in four rats exposed to fixed-time schedules of food ranging from 30 to 480 seconds. Herrnstein's (1970, 1974) equation relating rate of a single response as a hyperbolic function of reinforcement rate provided a good fit to three measures of drinking: lick rate, ingestion rate, and relative time spent drinking. The functions relating the three measures of drinking to reinforcement rate were of similar form. Herrnstein's equation also provided a good description of some already published data on schedule-induced drinking. The fit both to the present data and to the already published data was improved somewhat by computing the measures by subtracting from the time base a latency constant representing the minimal time required to consume the food pellet and travel to the water source. The data from this study provide two correspondences between operant behavior and schedule-induced behavior: (a) conformity to Herrnstein's equation and (b) equivalence of rate and relative time measures. PMID:512568

Rates of retinal nerve fibre layer thickness change in glaucoma patients and control subjects

PubMed Central

O'Leary, N; Artes, P H; Hutchison, D M; Nicolela, M T; Chauhan, B C

2012-01-01

Purpose To examine the rates of retinal nerve fibre layer thickness (RNFLT) change in glaucoma patients and healthy, age-similar control subjects with three techniques: scanning laser polarimetry with variable corneal compensation (VCC) and enhanced corneal compensation (ECC), and time-domain optical coherence tomography (OCT). Methods Sixty-one patients and thirty-three controls were examined with each technique and with standard automated perimetry (SAP) every 6 months. Rates of global RNFLT change and SAP mean deviation (MD) change were estimated with linear mixed-effects models. Results The median (interquartile range) baseline age was 64.4 (58.2, 71.0) years for patients and 62.4 (56.3, 70.1) years for controls (P=0.56). There was a median of seven examinations over 3.1 years for patients and six examinations in 3.0 years for controls. Baseline visual field MD and RNFLT for all imaging modalities were significantly lower (P<0.01) in patients compared with controls. Rates of RNFLT change were not significantly different between patients and controls (P≥0.19). Mean rates of VCC-measured RNFLT change were −0.18 and −0.37 μm per year in patients and controls, whereas the respective figures for ECC and OCT were −0.13 and −0.31 μm per year, and 0.04 and 0.61 μm per year. Mean rates of MD change were −0.20 and 0.03 dB per year in patients and controls, respectively (P=0.01). Conclusion Rates of RNFLT change in glaucoma patients were not statistically different from control subjects for any modality. A significantly negative rate of MD change in patients suggests a genuine, continued deterioration in these patients not reflected by RNFLT changes. PMID:23079756

Mathematical modeling of continuous ethanol fermentation in a membrane bioreactor by pervaporation compared to conventional system: Genetic algorithm.

PubMed

Esfahanian, Mehri; Shokuhi Rad, Ali; Khoshhal, Saeed; Najafpour, Ghasem; Asghari, Behnam

2016-07-01

In this paper, genetic algorithm was used to investigate mathematical modeling of ethanol fermentation in a continuous conventional bioreactor (CCBR) and a continuous membrane bioreactor (CMBR) by ethanol permselective polydimethylsiloxane (PDMS) membrane. A lab scale CMBR with medium glucose concentration of 100gL(-1) and Saccharomyces cerevisiae microorganism was designed and fabricated. At dilution rate of 0.14h(-1), maximum specific cell growth rate and productivity of 0.27h(-1) and 6.49gL(-1)h(-1) were respectively found in CMBR. However, at very high dilution rate, the performance of CMBR was quite similar to conventional fermentation on account of insufficient incubation time. In both systems, genetic algorithm modeling of cell growth, ethanol production and glucose concentration were conducted based on Monod and Moser kinetic models during each retention time at unsteady condition. The results showed that Moser kinetic model was more satisfactory and desirable than Monod model. Copyright © 2016 Elsevier Ltd. All rights reserved.

Morphological evolution of dissolving feldspar particles with anisotropic surface kinetics and implications for dissolution rate normalization and grain size dependence: A kinetic modeling study

NASA Astrophysics Data System (ADS)

Zhang, Li; Lüttge, Andreas

2009-11-01

With previous two-dimensional (2D) simulations based on surface-specific feldspar dissolution succeeding in relating the macroscopic feldspar kinetics to the molecular-scale surface reactions of Si and Al atoms ( Zhang and Lüttge, 2008, 2009), we extended our modeling effort to three-dimensional (3D) feldspar particle dissolution simulations. Bearing on the same theoretical basis, the 3D feldspar particle dissolution simulations have verified the anisotropic surface kinetics observed in the 2D surface-specific simulations. The combined effect of saturation state, pH, and temperature on the surface kinetics anisotropy has been subsequently evaluated, found offering diverse options for morphological evolution of dissolving feldspar nanoparticles with varying grain sizes and starting shapes. Among the three primary faces on the simulated feldspar surface, the (1 0 0) face has the biggest dissolution rate across an extensively wide saturation state range and thus acquires a higher percentage of the surface area upon dissolution. The slowest dissolution occurs to either (0 0 1) or (0 1 0) faces depending on the bond energies of Si-(O)-Si ( ΦSi-O-Si/ kT) and Al-(O)-Si ( ΦAl-O-Si/ kT). When the ratio of ΦSi-O-Si/ kT to ΦAl-O-Si/ kT changes from 6:3 to 7:5, the dissolution rates of three primary faces change from the trend of (1 0 0) > (0 1 0) > (0 0 1) to the trend of (1 0 0) > (0 0 1) > (0 1 0). The rate difference between faces becomes more distinct and accordingly edge rounding becomes more significant. Feldspar nanoparticles also experience an increasing degree of edge rounding from far-from-equilibrium to close-to-equilibrium. Furthermore, we assessed the connection between the continuous morphological modification and the variation in the bulk dissolution rate during the dissolution of a single feldspar particle. Different normalization treatments equivalent to the commonly used mass, cube assumption, sphere assumption, geometric surface area, and reactive surface area normalizations have been used to normalize the bulk dissolution rate. For each of the treatments, time consistence and grain size dependence of the normalized dissolution rate have been evaluated and the results revealed significant dependences on the magnitude of surface kinetic anisotropy under differing environmental conditions. In general, the normalized dissolution rates are strongly dependent on grain size. Time-consistent normalization treatment varies with the investigated condition. The modeling results suggest that the sphere-, cube-, and BET-normalized dissolution rates are appropriate under the far-from-equilibrium conditions at low pH where these normalizations are time-consistent and are slightly dependent on grain size.

Imbricated slip rate processes during slow slip transients imaged by low-frequency earthquakes

NASA Astrophysics Data System (ADS)

Lengliné, O.; Frank, W.; Marsan, D.; Ampuero, J. P.

2017-12-01

Low Frequency Earthquakes (LFEs) often occur in conjunction with transient strain episodes, or Slow Slip Events (SSEs), in subduction zones. Their focal mechanism and location consistent with shear failure on the plate interface argue for a model where LFEs are discrete dynamic ruptures in an otherwise slowly slipping interface. SSEs are mostly observed by surface geodetic instruments with limited resolution and it is likely that only the largest ones are detected. The time synchronization of LFEs and SSEs suggests that we could use the recorded LFEs to constrain the evolution of SSEs, and notably of the geodetically-undetected small ones. However, inferring slow slip rate from the temporal evolution of LFE activity is complicated by the strong temporal clustering of LFEs. Here we apply dedicated statistical tools to retrieve the temporal evolution of SSE slip rates from the time history of LFE occurrences in two subduction zones, Mexico and Cascadia, and in the deep portion of the San Andreas fault at Parkfield. We find temporal characteristics of LFEs that are similar across these three different regions. The longer term episodic slip transients present in these datasets show a slip rate decay with time after the passage of the SSE front possibly as t-1/4. They are composed of multiple short term transients with steeper slip rate decay as t-α with α between 1.4 and 2. We also find that the maximum slip rate of SSEs has a continuous distribution. Our results indicate that creeping faults host intermittent deformation at various scales resulting from the imbricated occurrence of numerous slow slip events of various amplitudes.

Imbricated slip rate processes during slow slip transients imaged by low-frequency earthquakes

NASA Astrophysics Data System (ADS)

Lengliné, O.; Frank, W. B.; Marsan, D.; Ampuero, J.-P.

2017-10-01

Low Frequency Earthquakes (LFEs) often occur in conjunction with transient strain episodes, or Slow Slip Events (SSEs), in subduction zones. Their focal mechanism and location consistent with shear failure on the plate interface argue for a model where LFEs are discrete dynamic ruptures in an otherwise slowly slipping interface. SSEs are mostly observed by surface geodetic instruments with limited resolution and it is likely that only the largest ones are detected. The time synchronization of LFEs and SSEs suggests that we could use the recorded LFEs to constrain the evolution of SSEs, and notably of the geodetically-undetected small ones. However, inferring slow slip rate from the temporal evolution of LFE activity is complicated by the strong temporal clustering of LFEs. Here we apply dedicated statistical tools to retrieve the temporal evolution of SSE slip rates from the time history of LFE occurrences in two subduction zones, Mexico and Cascadia, and in the deep portion of the San Andreas fault at Parkfield. We find temporal characteristics of LFEs that are similar across these three different regions. The longer term episodic slip transients present in these datasets show a slip rate decay with time after the passage of the SSE front possibly as t - 1 / 4. They are composed of multiple short term transients with steeper slip rate decay as t-α with α between 1.4 and 2. We also find that the maximum slip rate of SSEs has a continuous distribution. Our results indicate that creeping faults host intermittent deformation at various scales resulting from the imbricated occurrence of numerous slow slip events of various amplitudes.

A Hybrid Method of Moment Equations and Rate Equations to Modeling Gas-Grain Chemistry

NASA Astrophysics Data System (ADS)

Pei, Y.; Herbst, E.

2011-05-01

Grain surfaces play a crucial role in catalyzing many important chemical reactions in the interstellar medium (ISM). The deterministic rate equation (RE) method has often been used to simulate the surface chemistry. But this method becomes inaccurate when the number of reacting particles per grain is typically less than one, which can occur in the ISM. In this condition, stochastic approaches such as the master equations are adopted. However, these methods have mostly been constrained to small chemical networks due to the large amounts of processor time and computer power required. In this study, we present a hybrid method consisting of the moment equation approximation to the stochastic master equation approach and deterministic rate equations to treat a gas-grain model of homogeneous cold cloud cores with time-independent physical conditions. In this model, we use the standard OSU gas phase network (version OSU2006V3) which involves 458 gas phase species and more than 4000 reactions, and treat it by deterministic rate equations. A medium-sized surface reaction network which consists of 21 species and 19 reactions accounts for the productions of stable molecules such as H_2O, CO, CO_2, H_2CO, CH_3OH, NH_3 and CH_4. These surface reactions are treated by a hybrid method of moment equations (Barzel & Biham 2007) and rate equations: when the abundance of a surface species is lower than a specific threshold, say one per grain, we use the ``stochastic" moment equations to simulate the evolution; when its abundance goes above this threshold, we use the rate equations. A continuity technique is utilized to secure a smooth transition between these two methods. We have run chemical simulations for a time up to 10^8 yr at three temperatures: 10 K, 15 K, and 20 K. The results will be compared with those generated from (1) a completely deterministic model that uses rate equations for both gas phase and grain surface chemistry, (2) the method of modified rate equations (Garrod 2008), which partially takes into account the stochastic effect for surface reactions, and (3) the master equation approach solved using a Monte Carlo technique. At 10 K and standard grain sizes, our model results agree well with the above three methods, while discrepancies appear at higher temperatures and smaller grain sizes.

Method of Estimating Continuous Cooling Transformation Curves of Glasses

NASA Technical Reports Server (NTRS)

Zhu, Dongmei; Zhou, Wancheng; Ray, Chandra S.; Day, Delbert E.

2006-01-01

A method is proposed for estimating the critical cooling rate and continuous cooling transformation (CCT) curve from isothermal TTT data of glasses. The critical cooling rates and CCT curves for a group of lithium disilicate glasses containing different amounts of Pt as nucleating agent estimated through this method are compared with the experimentally measured values. By analysis of the experimental and calculated data of the lithium disilicate glasses, a simple relationship between the crystallized amount in the glasses during continuous cooling, X, and the temperature of undercooling, (Delta)T, was found to be X = AR(sup-4)exp(B (Delta)T), where (Delta)T is the temperature difference between the theoretical melting point of the glass composition and the temperature in discussion, R is the cooling rate, and A and B are constants. The relation between the amount of crystallisation during continuous cooling and isothermal hold can be expressed as (X(sub cT)/X(sub iT) = (4/B)(sup 4) (Delta)T(sup -4), where X(sub cT) stands for the crystallised amount in a glass during continuous cooling for a time t when the temperature comes to T, and X(sub iT) is the crystallised amount during isothermal hold at temperature T for a time t.

Insights into the origins of drumbeat earthquakes, periodic low frequency seismicity, and plug degradation from multi-instrument monitoring at Tungurahua volcano, Ecuador, April 2015

NASA Astrophysics Data System (ADS)

Bell, Andrew; Hernandez, Stephen; Gaunt, Elizabeth; Mothes, Patricia; Hidalgo, Silvana; Ruiz, Mario

2016-04-01

Highly-periodic repeating 'drumbeat' earthquakes have been reported from several andesitic and dacitic volcanoes. Physical models for the origin of drumbeat earthquakes incorporate, to different extents, the incremental upward movement of viscous magma. However, the roles played by stick-slip friction, brittle failure, and fluid flow, and the relations between drumbeat earthquakes and other low-frequency seismic signals, remain controversial. Here we report the results of analysis of three weeks of geophysical data recorded during an unrest episode at Tungurahua, an andesitic stratovolcano in Ecuador, during April 2015, by the monitoring network of the Instituto Geofisico of Ecuador. Combined seismic, geodetic, infrasound, and gas monitoring has provided new insights into the origins of periodic low-frequency seismic signals, conduit processes, and the nature of current unrest. Over the three-week period, the relative seismic amplitude (RSAM) correlated closely with short-term deformation rates and gas fluxes. However, the characteristics of the seismic signals, as recorded at a short-period station closest to the summit crater, changed considerably with time. Initially high RSAM and gas fluxes, with modest ash emissions, were associated with continuous and 'pulsed' tremor signals (amplitude modulated, with 30-100 second periods). As activity levels decreased over several days, tremor episodes became increasingly intermittent, and short-lived bursts of low-frequency earthquakes with quasiperiodic inter-event times were observed. Following one day of quiescence, the onset of pronounced low frequency drumbeat earthquakes signalled the resumption of elevated unrest, initially with mean inter-event times of 32 seconds, and later increasing to 74 seconds and longer, with periodicity progressively breaking down over several days. A reduction in RSAM was then followed by one week of persistent, quasiperiodic, longer-duration emergent low-frequency pulses, including 'double events'. The unrest finished with a series of minor explosions and ash emissions, and a reduction in RSAM. None of the seismic events were associated with significant infrasound or ground-coupled acoustic waves. The persistent and steadily evolving periodicity of seismic signals, and contemporaneous inflation-deflation tilt cycle, suggest that incremental upward movement of a viscous magma plug determines the system periodicity, likely controlled by the balance between magma ascent rate, magma compressibility beneath the plug, and resisting forces at the plug margin. However, relations between a range of observations, including waveform similarity, periodicity, and amplitudes of contemporaneous discrete and continuous signals, suggest that the detected seismic signals are predominantly generated by gas flow that is largely decoupled from the magma ascent rate. Signals are generated by both continuous flow through longer-lived pathways, and by gas pulses passing through transient pathways generated by slip at the plug margins. The nature and amplitude of signals is therefore a product of the rate of gas flux and the evolving state of the degassing pathway, controlled in part by degradation and healing of the plug margins.

High-speed wavelength-division multiplexing quantum key distribution system.

PubMed

Yoshino, Ken-ichiro; Fujiwara, Mikio; Tanaka, Akihiro; Takahashi, Seigo; Nambu, Yoshihiro; Tomita, Akihisa; Miki, Shigehito; Yamashita, Taro; Wang, Zhen; Sasaki, Masahide; Tajima, Akio

2012-01-15

A high-speed quantum key distribution system was developed with the wavelength-division multiplexing (WDM) technique and dedicated key distillation hardware engines. Two interferometers for encoding and decoding are shared over eight wavelengths to reduce the system's size, cost, and control complexity. The key distillation engines can process a huge amount of data from the WDM channels by using a 1 Mbit block in real time. We demonstrated a three-channel WDM system that simultaneously uses avalanche photodiodes and superconducting single-photon detectors. We achieved 12 h continuous key generation with a secure key rate of 208 kilobits per second through a 45 km field fiber with 14.5 dB loss.

The effects of feedback on computer workstation posture habits.

PubMed

Epstein, Rhonda; Colford, Sean; Epstein, Ethan; Loye, Brandon; Walsh, Michael

2012-01-01

Repetitive stress injuries (RSI) and musculoskeletal disorders in the United States and worldwide are increasing at an alarming rate due to the advent of ubiquitous computer usage. Factors that lead to computer-related musculoskeletal disorders (MSD) include inadequately designed workstations, poor posture, and lack of knowledge about proper ergonomics and use habits. Studies have documented the negative impact of improper posture and the MSD seen in students and office workers due to frequent computer usage. Determine if the frequency (single vs. continuous reminder) and/or use of feedback affects posture at a computer workstation. Observations of posture habits were made in three local schools and one local company. Feedback effects were tested on the students (ages 10-15). Real time feedback was given in two studies. In one study, instructions and a verbal reminder were given to students and in a second study, a prototype 'Posture Pad' was developed to provide continuous feedback to the user. Verbal reminders to sit correctly led to transient improvement of posture. Use of the 'Posture Pad' resulted in significant improvement in posture with subjects exhibiting correct posture 98 ± 5% of the time. Real time feedback about how one is sitting is an effective mechanism for non-transient improvement of posture at computer workstations.

Impedance spectroscopy and microstructural characterization of the corrosion behavior of FeCrAl alloy in lead-bismuth eutectic

NASA Astrophysics Data System (ADS)

Chen, Xiang; Haasch, Rick; Stubbins, James F.

2012-12-01

The corrosion behavior of FeCrAl alloy in Lead-Bismuth Eutectic (LBE) saturated with oxygen at 550 °C was investigated. Impedance Spectroscopy (IS) measurement was made continuously on one specimen during the entire LBE exposure test to characterize the corrosion kinetics. Various microanalysis techniques, including SEM, EDS, XRD, AES, and XPS were used to analyze the corrosion products of post-exposure specimens. It was found that a very thin, adherent alumina oxide layer formed on the specimen surface and was able to protect the alloy from the corrosion attack in LBE. The thickness of the alumina surface layer increased very slowly with time reaching about 837 nm in average thickness after exposure for 3600-h in LBE. The IS measurements match the microanalysis results in three respects: first, a non-zero impedance measurement agrees with the existence of a continuous surface oxide layer; second, a general increase of the impedance was observed during the real-time IS measurement which means that the IS measurements reflect the growth rate of the oxide layer; and third, the oxide film thickness derived from the IS data compares favorably with the SEM film thickness measurements which establishes the validity of using IS to monitor the real-time corrosion kinetics of alloys in LBE.

Effects of three types of trace element supplementation on the fertility of three commercial dairy herds.

PubMed

Black, D H; French, N P

2004-05-22

The effects on the fertility of three commercial dairy herds of three types of copper- and selenium-containing mineral supplements was investigated. As the cows on each farm were dried off they were allocated to one of three treatment groups, and treated with either subcutaneous injections of copper and selenium, or two matrix intraruminal trace element boluses, or two glass intraruminal trace element boluses. When the data from the 406 cows on the three farms were combined, there was a significant difference between the conception rates of the three groups (P < 0.001). The cows treated with the glass boluses conceived at a rate 1.8 times greater than those treated by injection (P < 0.001), and at a rate 1.5 times greater than those treated with matrix boluses (P = 0.002). These differences were associated with a significantly higher likelihood of service resulting in a conception in the group treated with glass boluses than in the group treated by injection (P = 0.004). After adjusting for time from calving, time from treatment, time of year and farm, there was a significant (P = 0.012) difference in glutathione peroxidase activities between the treatments, with the group treated by injection having a significantly lower activity than the groups treated with boluses.

Misery Loves Company? A Meta-Regression Examining Aggregate Unemployment Rates and the Unemployment-Mortality Association

PubMed Central

Roelfs, David J.; Shor, Eran; Blank, Aharon; Schwartz, Joseph E.

2015-01-01

PURPOSE Individual-level unemployment has been consistently linked to poor health and higher mortality, but some scholars have suggested that the negative effect of job loss may be lower during times and in places where aggregate unemployment rates are high. We review three logics associated with this moderation hypothesis: health selection, social isolation, and unemployment stigma. We then test whether aggregate unemployment rates moderate the individual-level association between unemployment and all-cause mortality. METHODS We use 6 meta-regression models (each utilizing a different measure of the aggregate unemployment rate) based on 62 relative all-cause mortality risk estimates from 36 studies (from 15 nations). RESULTS We find that the magnitude of the individual-level unemployment-mortality association is approximately the same during periods of high and low aggregate-level unemployment. Model coefficients (exponentiated) were 1.01 for the crude unemployment rate (p = 0.27), 0.94 for the change in unemployment rate from the previous year (p = 0.46), 1.01 for the deviation of the unemployment rate from the 5-year running average (p = 0.87), 1.01 for the deviation of the unemployment rate from the 10-year running average (p = 0.73), 1.01 for the deviation of the unemployment rate from the overall average (measured as a continuous variable; p = 0.61), and showed no variation across unemployment levels when the deviation of the unemployment rate from the overall average was measured categorically. Heterogeneity between studies was significant (p < .001), supporting the use of the random effects model. CONCLUSIONS We found no strong evidence to suggest that unemployment experiences change when macro-economic conditions change. Efforts to ameliorate the negative social and economic consequences of unemployment should continue to focus on the individual and should be maintained regardless of periodic changes in macro-economic conditions. PMID:25795225

Misery loves company? A meta-regression examining aggregate unemployment rates and the unemployment-mortality association.

PubMed

Roelfs, David J; Shor, Eran; Blank, Aharon; Schwartz, Joseph E

2015-05-01

Individual-level unemployment has been consistently linked to poor health and higher mortality, but some scholars have suggested that the negative effect of job loss may be lower during times and in places where aggregate unemployment rates are high. We review three logics associated with this moderation hypothesis: health selection, social isolation, and unemployment stigma. We then test whether aggregate unemployment rates moderate the individual-level association between unemployment and all-cause mortality. We use six meta-regression models (each using a different measure of the aggregate unemployment rate) based on 62 relative all-cause mortality risk estimates from 36 studies (from 15 nations). We find that the magnitude of the individual-level unemployment-mortality association is approximately the same during periods of high and low aggregate-level unemployment. Model coefficients (exponentiated) were 1.01 for the crude unemployment rate (P = .27), 0.94 for the change in unemployment rate from the previous year (P = .46), 1.01 for the deviation of the unemployment rate from the 5-year running average (P = .87), 1.01 for the deviation of the unemployment rate from the 10-year running average (P = .73), 1.01 for the deviation of the unemployment rate from the overall average (measured as a continuous variable; P = .61), and showed no variation across unemployment levels when the deviation of the unemployment rate from the overall average was measured categorically. Heterogeneity between studies was significant (P < .001), supporting the use of the random effects model. We found no strong evidence to suggest that unemployment experiences change when macroeconomic conditions change. Efforts to ameliorate the negative social and economic consequences of unemployment should continue to focus on the individual and should be maintained regardless of periodic changes in macroeconomic conditions. Copyright © 2015 Elsevier Inc. All rights reserved.

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

NASA Astrophysics Data System (ADS)

Kharchenko, Vyacheslav; Fesenko, Herman; Doukas, Nikos

2017-09-01

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

Short and long-term thermo-erosion of ice-rich permafrost coasts in the Laptev Sea region

NASA Astrophysics Data System (ADS)

Günther, F.; Overduin, P. P.; Sandakov, A. V.; Grosse, G.; Grigoriev, M. N.

2013-02-01

Permafrost coasts in the Arctic are susceptible to a variety of changing environmental factors all of which currently point to increasing coastal erosion rates and mass fluxes of sediment and carbon to the shallow arctic shelf seas. Rapid erosion along high yedoma coasts composed of Ice Complex permafrost deposits creates impressive coastal ice cliffs and inspired research for designing and implementing change detection studies for a long time, but continuous quantitative monitoring and a qualitative inventory of coastal thermo-erosion for large coastline segments is still lacking. Our goal is to use observations of thermo-erosion along the mainland coast of the Laptev Sea in eastern Siberia to understand how erosion rates depend on coastal geomorphology and the relative contributions of waterline and atmospheric drivers to coastal thermo-erosion over the past 4 decades and in the past few years. We compared multitemporal sets of orthorectified satellite imagery from 1965 to 2011 for three segments of coastline with a length of 73 to 95 km each and analyzed thermo-denudation (TD) along cliff top and thermo-abrasion (TA) along cliff bottom for two nested time periods: long-term rates (the past 39-43 yr) and short term rates (the past 1-3 yr). The Normalized Difference Thermo-erosion Index (NDTI) was used as a proxy that qualitatively describes the relative proportions of TD and TA. Mean annual erosion rates at all three sites were higher in recent years (-5.3 ± 1.31 m a-1) than over the long term mean (-2.2 ± 0.13 m a-1). The Mamontov Klyk coast exhibit primarily spatial variations of thermo-erosion, while intrasite-specific variations were strongest at the Buor Khaya coast, where slowest long-term rates around -0.5 ± 0.08 m a-1 were observed. The Oyogos Yar coast showed continuously rapid erosion up to -6.5 ± 0.19 m a-1. In general, variable characteristics of coastal thermo-erosion were observed not only between study sites and over time, but also within single coastal transects along the cliff profile. Varying intensities of cliff bottom and top retreat are leading to diverse qualities of coastal erosion that have different impacts on coastal mass fluxes. The different extents of Ice Complex permafrost degradation within our study sites turned out to influence not only the degree of coupling between TD and TA, and the magnitude of effectively eroded volumes, but also the quantity of organic carbon released to the shallow Laptev Sea from coastal erosion, which ranged on a long-term from 88 ± 21.0 to 800 ± 61.1 t per km coastline per year and will correspond to considerably higher amounts, if recently observed more rapid coastal erosion rates prove to be persistent.

Teaching Students to Request the Continuation of Routine Activities by Using Time Delay and Decreasing Physical Assistance in the Context of Chain Interruption.

ERIC Educational Resources Information Center

Gee, Kathleen; And Others

1991-01-01

Three students (ages 5-10) with profound intellectual, sensory, and physical disabilities were taught to activate a communication device to request the continuation of activities in which they were involved. The intervention consisted of a consistent response interval and increasing time delay paired with decreasing physical assistance in…

Modeling the Hot Tensile Flow Behaviors at Ultra-High-Strength Steel and Construction of Three-Dimensional Continuous Interaction Space for Forming Parameters

NASA Astrophysics Data System (ADS)

Quan, Guo-zheng; Zhan, Zong-yang; Wang, Tong; Xia, Yu-feng

2017-01-01

The response of true stress to strain rate, temperature and strain is a complex three-dimensional (3D) issue, and the accurate description of such constitutive relationships significantly contributes to the optimum process design. To obtain the true stress-strain data of ultra-high-strength steel, BR1500HS, a series of isothermal hot tensile tests were conducted in a wide temperature range of 973-1,123 K and a strain rate range of 0.01-10 s-1 on a Gleeble 3800 testing machine. Then the constitutive relationships were modeled by an optimally constructed and well-trained backpropagation artificial neural network (BP-ANN). The evaluation of BP-ANN model revealed that it has admirable performance in characterizing and predicting the flow behaviors of BR1500HS. A comparison on improved Arrhenius-type constitutive equation and BP-ANN model shows that the latter has higher accuracy. Consequently, the developed BP-ANN model was used to predict abundant stress-strain data beyond the limited experimental conditions. Then a 3D continuous interaction space for temperature, strain rate, strain and stress was constructed based on these predicted data. The developed 3D continuous interaction space for hot working parameters contributes to fully revealing the intrinsic relationships of BR1500HS steel.

A fiber-based quasi-continuous-wave quantum key distribution system

PubMed Central

Shen, Yong; Chen, Yan; Zou, Hongxin; Yuan, Jianmin

2014-01-01

We report a fiber-based quasi-continuous-wave (CW) quantum key distribution (QKD) system with continuous variables (CV). This system employs coherent light pulses and time multiplexing to maximally reduce cross talk in the fiber. No-switching detection scheme is adopted to optimize the repetition rate. Information is encoded on the sideband of the pulsed coherent light to fully exploit the continuous wave nature of laser field. With this configuration, high secret key rate can be achieved. For the 50 MHz detected bandwidth in our experiment, when the multidimensional reconciliation protocol is applied, a secret key rate of 187 kb/s can be achieved over 50 km of optical fiber against collective attacks, which have been shown to be asymptotically optimal. Moreover, recently studied loopholes have been fixed in our system. PMID:24691409

Chemoprevention of Skin Cancer Program Project | Division of Cancer Prevention

Cancer.gov

DESCRIPTION (provided by applicant): Skin cancer is the most common malignancy in the world. One out of three new cancers is a skin cancer. More than 1 million cases of non-melanoma skin cancer (NMSC) (basal cell carcinoma [BCC] and squamous cell cancers [SCC]) occur annually. While the incidence rates for non-melanoma skin cancers continue to rise, there continues to be a

Impact of Flood Spates on Denitrifying Bacteria in Low Order Streams

NASA Astrophysics Data System (ADS)

Herrman, K.; Stokdyk, J.

2011-12-01

The impact of flood events on channel design, macroinvertebrates, and periphyton in stream ecosystems has been well studied. Little is known, however, about how flood spates affect microorganisms found in stream sediments. Denitrifying bacteria are beneficial organisms because they convert nitrates to nitrogen gas. Providing data that describes the impact of flood events on denitrifiers and the time required after the disturbance for the bacteria to recover are crucial in understanding nitrogen dynamics in stream ecosystems. Three low order streams in central Wisconsin, USA are being monitored during several flood spates during July and August of 2011. Discharge is being continuously monitored in all three streams and sediments are being collected before and after several flood events for laboratory assays. Specifically, sediments are being processed for denitrification rates using the acetylene inhibition technique, microbial biomass carbon using chloroform fumigation, and the quantification of denitrifying bacteria (i.e., nirS, nirK, and nosZ genes) using real-time quantitative PCR. Preliminary data show that within 36 hours after a 90 mm rain event, microbial biomass carbon in all three streams (580 μg C g sediment-1) significantly increased (F1,23 = 650 ± 140; p < 0.001) compared to microbial biomass during baseflow (200 ± 27 μg C g sediment-1). These initial results suggest that contrary to our expectations flood events enhance bacteria in stream sediments. Denitrification rates and quantification of denitrifying bacteria still need to be analyzed to determine if these specific bacteria follow a similar pattern or if the bacterial recolonization of stream sediments follows a unique pattern.

Using a time-series statistical framework to quantify trends and abrupt change in US corn, soybean, and wheat yields from 1970-2016

NASA Astrophysics Data System (ADS)

Zhang, J.; Ives, A. R.; Turner, M. G.; Kucharik, C. J.

2017-12-01

Previous studies have identified global agricultural regions where "stagnation" of long-term crop yield increases has occurred. These studies have used a variety of simple statistical methods that often ignore important aspects of time series regression modeling. These methods can lead to differing and contradictory results, which creates uncertainty regarding food security given rapid global population growth. Here, we present a new statistical framework incorporating time series-based algorithms into standard regression models to quantify spatiotemporal yield trends of US maize, soybean, and winter wheat from 1970-2016. Our primary goal was to quantify spatial differences in yield trends for these three crops using USDA county level data. This information was used to identify regions experiencing the largest changes in the rate of yield increases over time, and to determine whether abrupt shifts in the rate of yield increases have occurred. Although crop yields continue to increase in most maize-, soybean-, and winter wheat-growing areas, yield increases have stagnated in some key agricultural regions during the most recent 15 to 16 years: some maize-growing areas, except for the northern Great Plains, have shown a significant trend towards smaller annual yield increases for maize; soybean has maintained an consistent long-term yield gains in the Northern Great Plains, the Midwest, and southeast US, but has experienced a shift to smaller annual increases in other regions; winter wheat maintained a moderate annual increase in eastern South Dakota and eastern US locations, but showed a decline in the magnitude of annual increases across the central Great Plains and western US regions. Our results suggest that there were abrupt shifts in the rate of annual yield increases in a variety of US regions among the three crops. The framework presented here can be broadly applied to additional yield trend analyses for different crops and regions of the Earth.

Transpiration and CO/sub 2/ fixation of selected desert shrubs as related to soil-water potential

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

Clark, S.B.; Letey, J. Jr.; Lunt, O.R.

1980-01-01

In desert plants, transpiration rates decreased before photosynthetic rates when plants were entering a period of water stress. This may have adaptive consequences. A difference of -5 bars in the soil-moisture potential had considerable importance in reducing the rate of transpiration. In Helianthus annuus L. (sunflower) the photosynthetic rate decreased before the transpiration rate in contrast to Great Basin-Mojave Desert plants, and the changes occurred with a -1 bar difference in soil-moisture potential. Morphological changes in three desert plant species (Artemisia tridentata Nutt., Ambrosia dumosa (Gray) Payne, Larrea tridentata (Ses. Moc. ex DC) Cov.) as the soil-moisture potential decreased aremore » given. With a mesic species, H. annuus, 20% reduction in photosynthesis and transpiration was reached at higher soil-moisture potentials than with the desert plants. Loss of net photosynthesis occurred in A. dumosa (a summer deciduous shrub) as PSI soil reached -48 bars in the field, whereas L. tridentata (an evergreen shrub) at the same time was able to maintain a water potential difference between soil and plant of -10 to -15 bars and continue net CO/sub 2/ gain well into the summer months.« less

Not seeking yet trying long-acting reversible contraception: a 24-month randomized trial on continuation, unintended pregnancy and satisfaction.

PubMed

Hubacher, David; Spector, Hannah; Monteith, Charles; Chen, Pai-Lien

2018-06-01

To measure the 24-month impact on continuation, unintended pregnancy and satisfaction of trying long-acting reversible contraception (LARC) in a population seeking short-acting reversible contraception (SARC). We enrolled 916 women aged 18-29 who were seeking pills or injectables in a partially randomized patient preference trial. Women with strong preferences for pills or injectables started on those products, while others opted for randomization to LARC or SARC and received their methods gratis. We estimated continuation and unintended pregnancy rates through 24months. Intent-to-treat principles were applied after method initiation for comparing incidence of unintended pregnancy. We also examined how satisfaction levels varied by cohort and how baseline negative LARC attitudes were associated with satisfaction over time. Forty-three percent chose randomization, and 57% chose the preference option. Complete loss to follow-up was<2%. The 24-month LARC continuation probability was 64.3% [95% confidence interval (CI): 56.6-70.9], statistically higher than SARC groups [25.5% (randomized) and 40.0% (preference)]. The 24-month cumulative unintended pregnancy probabilities were 9.9% (95% CI: 7.2-12.6) (preference-SARC), 6.9% (95% CI: 3.3-10.6) (randomized-SARC) and 3.6% (95% CI: 1.8-6.4) (randomized-LARC). Statistical tests for comparing randomized groups on unintended pregnancy were mixed: binomial at 24-month time point (p=.02) and log-rank survival probabilities (p=.14 for first pregnancies and p=.07 when including second pregnancies). LARC satisfaction was high (80% happy/neutral, 73% would use LARC again, 81% would recommend to a friend). Baseline negative attitudes toward LARC (27%) were not clearly associated with satisfaction or early discontinuation. The decision to try LARC resulted in high continuation rates and substantial protection from unintended pregnancy over 24months. Despite participants' initial desires to begin short-acting regimens, they had high satisfaction with LARC. Voluntary decisions to try LARC will benefit large proportions of typical SARC users. Even women who do not necessarily view LARC as a first choice may have a highly satisfying experience and avoid unintended pregnancy if they try it. Copyright © 2018 Elsevier Inc. All rights reserved.

Treatment of menopausal symptoms with three low-dose continuous sequential 17β-estradiol/progesterone parenteral monthly formulations using novel non-polymeric microsphere technology

PubMed Central

Cortés-Bonilla, Manuel; Bernardo-Escudero, Roberto; Alonso-Campero, Rosalba; Francisco-Doce, María T.; Hernández-Valencia, Marcelino; Celis-González, Cuauhtémoc; Márquez-Oñate, Ricardo; Chedraui, Peter; Uribe, Juan A.

2015-01-01

Abstract Objective: To analyze the short-term efficacy and safety over menopausal symptoms of three low-dose continuous sequential 17β-estradiol (E)/progesterone (P) parental monthly formulations using novel non-polymeric microspheres. Methods: This was a multicenter, randomized, single blinded study in which peri- and postmenopausal women were assigned to receive a monthly intramuscular injection of 0.5 mg E + 15 mg P (Group A, n = 34), 1 mg E + 20 mg P (Group B, n = 24) or 1 mg E + 30 mg P (Group C, n = 26) for 6 months. Primary efficacy endpoints included mean change in the frequency and severity of hot flushes and the effect over urogenital atrophy symptoms at 3 and 6 months. Safety variables included changes in the rate of amenorrhea, endometrial thickness and histopathology, and local and systemic adverse events. Results: Compared to baseline at month 6, the three treatment schemes significantly decreased the rate of urogenital atrophy symptoms and the frequency (mean number per day) and severity (mean number graded as moderate and severe per month) of hot flushes. No differences in studied efficacy parameters were observed between studied groups at baseline or at the end of the study. For all groups the most frequent adverse event was pain at the injection site; however they were all rated as mild. At the end of the study peri- and postmenopausal women displayed no significant changes in endometrial thickness or histopathology in all treated groups. The rate of amenorrhea at the end of the study decreased for all studied groups yet was less evident among postmenopausal women as compared to perimenopausal ones. Conclusions: The three low-dose continuous sequential intramuscular monthly treatments of E/P using novel microsphere technology were effective at reducing menopausal symptoms at short-term with a low rate of adverse events. More long-term and comparative research is warranted to support our positive findings. PMID:26062108

Discrete rational and breather solution in the spatial discrete complex modified Korteweg-de Vries equation and continuous counterparts.

PubMed

Zhao, Hai-Qiong; Yu, Guo-Fu

2017-04-01

In this paper, a spatial discrete complex modified Korteweg-de Vries equation is investigated. The Lax pair, conservation laws, Darboux transformations, and breather and rational wave solutions to the semi-discrete system are presented. The distinguished feature of the model is that the discrete rational solution can possess new W-shape rational periodic-solitary waves that were not reported before. In addition, the first-order rogue waves reach peak amplitudes which are at least three times of the background amplitude, whereas their continuous counterparts are exactly three times the constant background. Finally, the integrability of the discrete system, including Lax pair, conservation laws, Darboux transformations, and explicit solutions, yields the counterparts of the continuous system in the continuum limit.

20 CFR 10.216 - How is the pay rate for COP calculated?

Code of Federal Regulations, 2012 CFR

2012-04-01

... 20 Employees' Benefits 1 2012-04-01 2012-04-01 false How is the pay rate for COP calculated? 10..., AS AMENDED Continuation of Pay Calculation of Cop § 10.216 How is the pay rate for COP calculated? The employer shall calculate COP using the period of time and the weekly pay rate. (a) The pay rate...

Sorption of Heterotrophic and Enteric Bacteria to Glass Surfaces in the Continuous Culture of River Water

PubMed Central

Hendricks, Charles W.

1974-01-01

A natural population of heterotrophic bacteria, including enterics, was observed to sorb to glass surfaces and multiply during the continuous culture of river water. An initial rate of attachment equivalent to a doubling time of about 2 h was observed with a corresponding increase in the suspended population. After 24 h both the sorbed and suspended populations stabilized with a mass doubling time approximating 100 h at a dilution rate of 0.012/h. On the basis of respiration and degradative enzymatic data, the sorbed microorganisms appeared to be somewhat more metabolically active than the organisms in suspension. PMID:4424694

Continuous microbial cultures maintained by electronically-controlled device

NASA Technical Reports Server (NTRS)

Eisler, W. J., Jr.; Webb, R. B.

1967-01-01

Photocell-controlled instrument maintains microbial culture. It uses commercially available chemostat glassware, provides adequate aeration through bubbling of the culture, maintains the population size and density, continuously records growth rates over small increments of time, and contains a simple, sterilizable nutrient control mechanism.

Effect of intermittent eccentric contractions on symptoms of muscle microinjury.

PubMed

Teague, B N; Schwane, J A

1995-10-01

The purpose was to determine whether varying the duration of rest between contractions affects selected symptoms of eccentric contraction-induced skeletal muscle microinjury. Thirty-three women were assigned to three groups (N = 11). Each performed one bout of exercise with each arm involving 10 eccentric contractions of the elbow flexor muscles, lowering a load equaling 60% of maximal static force. One arm exercised continuously; the other exercised with rest periods of 15 s, 5 min, or 10 min between contractions, depending on the group. Preexercise and 0, 24, and 48 h postexercise, symptoms of microinjury in the elbow flexor muscles were assessed: soreness and changes in strength, resting elbow angle ("musculotendinous stiffness"), and arm girth ("swelling"). For all groups combined, 10 continuous contractions caused changes (P < 0.05) in all variables at every measurement time. For example, soreness ratings (0-10 scale) were 4.3 +/- 2.0 (24 h) and 4.3 +/- 2.1 (48 h) and strength was reduced 18% 0 h postexercise. Responses were similar with 15 s of rest between contractions. Although they were moderated, symptoms occurred even with 5 and 10 min of rest. With 10 min between contractions, soreness occurred (e.g., 2.4 +/- 1.5 [24 h]) and strength was 17% reduced 0 h postexercise. Results are most consistent with a mechanical cause of eccentric contraction-induced muscle microinjury, rather than a metabolic or other factor with a short recovery time, although involvement of the latter cannot be ruled out.

Randomised prospective parallel trial of therapeutic versus subtherapeutic nasal continuous positive airway pressure on simulated steering performance in patients with obstructive sleep apnoea

PubMed Central

Hack, M.; Davies, R.; Mullins, R.; Choi, S. J.; Ramdassingh-Dow, S.; Jenkinson, C.; Stradling, J.

2000-01-01

BACKGROUND—Obstructive sleep apnoea (OSA) impairs vigilance and may lead to an increased rate of driving accidents. In uncontrolled studies accident rates and simulated steering performance improve following treatment with nasal continuous positive airway pressure (NCPAP). This study seeks to confirm the improvement in steering performance in a randomised controlled trial using subtherapeutic NCPAP as a control treatment.
METHODS—Fifty nine men with OSA (Epworth Sleepiness Score (ESS) of ⩾10, and ⩾10/h dips in SaO2 of >4% due to OSA) received therapeutic or subtherapeutic NCPAP (≈1 cm H2O) for one month. Simulated steering performance over three 30-minute "drives" was quantified as: standard deviation (SD) of road position, deterioration in SD across the drive, length of drive before "crashing", and number of off-road events. The reaction times to peripheral target stimuli during the drive were also measured.
RESULTS—Subtherapeutic NCPAP did not improve overnight >4% SaO2 dips/h compared with baseline values, thus acting as a control. The SD of the steering position improved from 0.36 to 0.21 on therapeutic NCPAP, and from 0.35 to 0.30 on subtherapeutic NCPAP (p = 0.03). Deterioration in SD of the steering position improved from 0.18to 0.06 SD/h with therapeutic NCPAP and worsened from 0.18 to 0.24 with subtherapeutic NCPAP (p = 0.04). The reaction time to target stimuli was quicker after therapeutic than after subtherapeutic NCPAP (2.3 versus 2.7 seconds, p = 0.04).
CONCLUSIONS—Therapeutic NCPAP improves steering performance and reaction time to target stimuli in patients with OSA, lending further support to the hypothesis that OSA impairs driving, increases driving accident rates, and that these improve following treatment with NCPAP.

 PMID:10679542

Can volunteering in later life reduce the risk of dementia? A 5-year longitudinal study among volunteering and non-volunteering retired seniors.

PubMed

Griep, Yannick; Hanson, Linda Magnusson; Vantilborgh, Tim; Janssens, Laurens; Jones, Samantha K; Hyde, Martin

2017-01-01

We propose that voluntary work, characterized by social, physical and cognitive activity in later life is associated with fewer cognitive problems and lower dementia rates. We test these assumptions using 3-wave, self-reported, and registry data from the 2010, 2012, and 2014 Swedish National Prescribed Drug Register. We had three groups of seniors in our data: 1) no volunteering (N = 531), 2) discontinuous volunteering (N = 220), and 3) continuous volunteering (N = 250). We conducted a path analysis in Mplus to investigate the effect of voluntary work (discontinuously and continuously) on self-reported cognitive complaints and the likelihood of being prescribed an anti-dementia treatment after controlling for baseline and relevant background variables. Our results indicated that seniors, who continuously volunteered, reported a decrease in their cognitive complaints over time, whereas no such associations were found for the other groups. In addition, they were 2.44 (95%CI [1.86; 3.21]) and 2.46 (95%CI [1,89; 3.24]) times less likely to be prescribed an anti-dementia treatment in 2012 and 2014, respectively. Our results largely support the assumptions that voluntary work in later life is associated with lower self-reported cognitive complaints and a lower risk for dementia, relative to those who do not engage, or only engage episodically in voluntary work.

Can volunteering in later life reduce the risk of dementia? A 5-year longitudinal study among volunteering and non-volunteering retired seniors

PubMed Central

Hanson, Linda Magnusson; Vantilborgh, Tim; Janssens, Laurens; Jones, Samantha K.; Hyde, Martin

2017-01-01

We propose that voluntary work, characterized by social, physical and cognitive activity in later life is associated with fewer cognitive problems and lower dementia rates. We test these assumptions using 3-wave, self-reported, and registry data from the 2010, 2012, and 2014 Swedish National Prescribed Drug Register. We had three groups of seniors in our data: 1) no volunteering (N = 531), 2) discontinuous volunteering (N = 220), and 3) continuous volunteering (N = 250). We conducted a path analysis in Mplus to investigate the effect of voluntary work (discontinuously and continuously) on self-reported cognitive complaints and the likelihood of being prescribed an anti-dementia treatment after controlling for baseline and relevant background variables. Our results indicated that seniors, who continuously volunteered, reported a decrease in their cognitive complaints over time, whereas no such associations were found for the other groups. In addition, they were 2.44 (95%CI [1.86; 3.21]) and 2.46 (95%CI [1,89; 3.24]) times less likely to be prescribed an anti-dementia treatment in 2012 and 2014, respectively. Our results largely support the assumptions that voluntary work in later life is associated with lower self-reported cognitive complaints and a lower risk for dementia, relative to those who do not engage, or only engage episodically in voluntary work. PMID:28301554

Quantifying the uncertainty in discharge data using hydraulic knowledge and uncertain gaugings: a Bayesian method named BaRatin

NASA Astrophysics Data System (ADS)

Le Coz, Jérôme; Renard, Benjamin; Bonnifait, Laurent; Branger, Flora; Le Boursicaud, Raphaël; Horner, Ivan; Mansanarez, Valentin; Lang, Michel; Vigneau, Sylvain

2015-04-01

River discharge is a crucial variable for Hydrology: as the output variable of most hydrologic models, it is used for sensitivity analyses, model structure identification, parameter estimation, data assimilation, prediction, etc. A major difficulty stems from the fact that river discharge is not measured continuously. Instead, discharge time series used by hydrologists are usually based on simple stage-discharge relations (rating curves) calibrated using a set of direct stage-discharge measurements (gaugings). In this presentation, we present a Bayesian approach (cf. Le Coz et al., 2014) to build such hydrometric rating curves, to estimate the associated uncertainty and to propagate this uncertainty to discharge time series. The three main steps of this approach are described: (1) Hydraulic analysis: identification of the hydraulic controls that govern the stage-discharge relation, identification of the rating curve equation and specification of prior distributions for the rating curve parameters; (2) Rating curve estimation: Bayesian inference of the rating curve parameters, accounting for the individual uncertainties of available gaugings, which often differ according to the discharge measurement procedure and the flow conditions; (3) Uncertainty propagation: quantification of the uncertainty in discharge time series, accounting for both the rating curve uncertainties and the uncertainty of recorded stage values. The rating curve uncertainties combine the parametric uncertainties and the remnant uncertainties that reflect the limited accuracy of the mathematical model used to simulate the physical stage-discharge relation. In addition, we also discuss current research activities, including the treatment of non-univocal stage-discharge relationships (e.g. due to hydraulic hysteresis, vegetation growth, sudden change of the geometry of the section, etc.). An operational version of the BaRatin software and its graphical interface are made available free of charge on request to the authors. J. Le Coz, B. Renard, L. Bonnifait, F. Branger, R. Le Boursicaud (2014). Combining hydraulic knowledge and uncertain gaugings in the estimation of hydrometric rating curves: a Bayesian approach, Journal of Hydrology, 509, 573-587.

Heart Rate Detection During Sleep Using a Flexible RF Resonator and Injection-Locked PLL Sensor.

PubMed

Kim, Sung Woo; Choi, Soo Beom; An, Yong-Jun; Kim, Byung-Hyun; Kim, Deok Won; Yook, Jong-Gwan

2015-11-01

Novel nonintrusive technologies for wrist pulse detection have been developed and proposed as systems for sleep monitoring using three types of radio frequency (RF) sensors. The three types of RF sensors for heart rate measurement on wrist are a flexible RF single resonator, array resonators, and an injection-locked PLL resonator sensor. To verify the performance of the new RF systems, we compared heart rates between presleep time and postsleep onset time. Heart rates of ten subjects were measured using the RF systems during sleep. All three RF devices detected heart rates at 0.2 to 1 mm distance from the skin of the wrist over clothes made of cotton fabric. The wrist pulse signals of a flexible RF single resonator were consistent with the signals obtained by a portable piezoelectric transducer as a reference. Then, we confirmed that the heart rate after sleep onset time significantly decreased compared to before sleep. In conclusion, the RF system can be utilized as a noncontact nonintrusive method for measuring heart rates during sleep.

Kangaroo mother care diminishes pain from heel lance in very preterm neonates: a crossover trial.

PubMed

Johnston, C Celeste; Filion, Francoise; Campbell-Yeo, Marsha; Goulet, Celine; Bell, Linda; McNaughton, Kathryn; Byron, Jasmine; Aita, Marilyn; Finley, G Allen; Walker, Claire-Dominique

2008-04-24

Skin-to-skin contact, or kangaroo mother care (KMC) has been shown to be efficacious in diminishing pain response to heel lance in full term and moderately preterm neonates. The purpose of this study was to determine if KMC would also be efficacious in very preterm neonates. Preterm neonates (n = 61) between 28 0/7 and 31 6/7 weeks gestational age in three Level III NICU's in Canada comprised the sample. A single-blind randomized crossover design was employed. In the experimental condition, the infant was held in KMC for 15 minutes prior to and throughout heel lance procedure. In the control condition, the infant was in prone position swaddled in a blanket in the incubator. The primary outcome was the Premature Infant Pain Profile (PIPP), which is comprised of three facial actions, maximum heart rate, minimum oxygen saturation levels from baseline in 30-second blocks from heel lance. The secondary outcome was time to recover, defined as heart rate return to baseline. Continuous video, heart rate and oxygen saturation monitoring were recorded with event markers during the procedure and were subsequently analyzed. Repeated measures analysis-of-variance was employed to generate results. PIPP scores at 90 seconds post lance were significantly lower in the KMC condition (8.871 (95%CI 7.852-9.889) versus 10.677 (95%CI 9.563-11.792) p < .001) and non-significant mean differences ranging from 1.2 to1.8. favoring KMC condition at 30, 60 and 120 seconds. Time to recovery was significantly shorter, by a minute(123 seconds (95%CI 103-142) versus 193 seconds (95%CI 158-227). Facial actions were highly significantly lower across all points in time reaching a two-fold difference by 120 seconds post-lance and heart rate was significantly lower across the first 90 seconds in the KMC condition. Very preterm neonates appear to have endogenous mechanisms elicited through skin-to-skin maternal contact that decrease pain response, but not as powerfully as in older preterm neonates. The shorter recovery time in KMC is clinically important in helping maintain homeostasis. (Current Controlled Trials) ISRCTN63551708.

Dynamic strain and rotation ground motions of the 2011 Tohoku earthquake from dense high-rate GPS observations in Taiwan

NASA Astrophysics Data System (ADS)

Huang, B. S.; Rau, R. J.; Lin, C. J.; Kuo, L. C.

2017-12-01

Seismic waves generated by the 2011 Mw 9.0 Tohoku, Japan earthquake were well recorded by continuous GPS in Taiwan. Those GPS were operated in one hertz sampling rate and densely distributed in Taiwan Island. Those continuous GPS observations and the precise point positioning technique provide an opportunity to estimate spatial derivatives from absolute ground motions of this giant teleseismic event. In this study, we process and investigate more than one and half hundred high-rate GPS displacements and its spatial derivatives, thus strain and rotations, to compare to broadband seismic and rotational sensor observations. It is shown that continuous GPS observations are highly consistent with broadband seismic observations during its surface waves across Taiwan Island. Several standard Geodesy and seismic array analysis techniques for spatial gradients have been applied to those continuous GPS time series to determine its dynamic strain and rotation time histories. Results show that those derivate GPS vertical axis ground rotations are consistent to seismic array determined rotations. However, vertical rotation-rate observations from the R1 rotational sensors have low resolutions and could not compared with GPS observations for this special event. For its dese spatial distribution of GPS stations in Taiwan Island, not only wavefield gradient time histories at individual site was obtained but also 2-D spatial ground motion fields were determined in this study also. In this study, we will report the analyzed results of those spatial gradient wavefields of the 2011 Tohoku earthquake across Taiwan Island and discuss its geological implications.

A Kinetic Study of the Effect of Basicity on the Mold Fluxes Crystallization

NASA Astrophysics Data System (ADS)

Zhou, Lejun; Wang, Wanlin; Ma, Fanjun; Li, Jin; Wei, Juan; Matsuura, Hiroyuki; Tsukihashi, Fumitaka

2012-04-01

The effect of basicity on the mold fluxes crystallization was investigated in this article. The time-temperature-transformation (TTT) diagrams and continuous-cooling-transformation (CCT) diagrams of mold fluxes with different basicity were constructed by using single, hot thermocouple technology (SHTT). The results showed that with the increase of basicity, the incubation time of isothermal crystallization became shorter, the crystallization temperature was getting higher, and the critical cooling rate of continuous cooling crystallization became faster. The X-ray diffraction analysis suggested that calcium silicate (CaO·SiO2) was precipitated at the upper part of the TTT diagram and cuspidine (Ca4Si2O7F2) was formed at the lower part, when the basicity of mold fluxes was within 1.0 to 1.2. However, when basicity was 0.8, only the cuspidine phase was formed. A kinetic study of isothermal crystallization process indicated that the increase of the basicity tended to enhance the mold flux crystallization, and the crystallization activation energy became smaller. The crystallization mechanism of cupsidine was changing from one-dimensional growth to three-dimensional growth with a constant number of nuclei, when the basicity of mold fluxes varied from 0.8 to 1.2.

Stress reaction process-based hierarchical recognition algorithm for continuous intrusion events in optical fiber prewarning system

NASA Astrophysics Data System (ADS)

Qu, Hongquan; Yuan, Shijiao; Wang, Yanping; Yang, Dan

2018-04-01

To improve the recognition performance of optical fiber prewarning system (OFPS), this study proposed a hierarchical recognition algorithm (HRA). Compared with traditional methods, which employ only a complex algorithm that includes multiple extracted features and complex classifiers to increase the recognition rate with a considerable decrease in recognition speed, HRA takes advantage of the continuity of intrusion events, thereby creating a staged recognition flow inspired by stress reaction. HRA is expected to achieve high-level recognition accuracy with less time consumption. First, this work analyzed the continuity of intrusion events and then presented the algorithm based on the mechanism of stress reaction. Finally, it verified the time consumption through theoretical analysis and experiments, and the recognition accuracy was obtained through experiments. Experiment results show that the processing speed of HRA is 3.3 times faster than that of a traditional complicated algorithm and has a similar recognition rate of 98%. The study is of great significance to fast intrusion event recognition in OFPS.

Continuous formation of N-chloro-N,N-dialkylamine solutions in well-mixed meso-scale flow reactors

PubMed Central

Jolley, Katherine E

2015-01-01

Summary The continuous flow synthesis of a range of organic solutions of N,N-dialkyl-N-chloramines is described using either a bespoke meso-scale tubular reactor with static mixers or a continuous stirred tank reactor. Both reactors promote the efficient mixing of a biphasic solution of N,N-dialkylamine in organic solvent, and aqueous sodium hypochlorite to achieve near quantitative conversions, in 72–100% in situ yields, and useful productivities of around 0.05 mol/h with residence times from 3 to 20 minutes. Initial calorimetric studies have been carried out to inform on reaction exotherms, rates and safe operation. Amines which partition mainly in the organic phase require longer reaction times, provided by the CSTR, to compensate for low mass transfer rates in the biphasic system. The green metrics of the reaction have been assessed and compared to existing procedures and have shown the continuous process is improved over previous procedures. The organic solutions of N,N-dialkyl-N-chloramines produced continuously will enable their use in tandem flow reactions with a range of nucleophilic substrates. PMID:26734089

Modeling multiple time series annotations as noisy distortions of the ground truth: An Expectation-Maximization approach.

PubMed

Gupta, Rahul; Audhkhasi, Kartik; Jacokes, Zach; Rozga, Agata; Narayanan, Shrikanth

2018-01-01

Studies of time-continuous human behavioral phenomena often rely on ratings from multiple annotators. Since the ground truth of the target construct is often latent, the standard practice is to use ad-hoc metrics (such as averaging annotator ratings). Despite being easy to compute, such metrics may not provide accurate representations of the underlying construct. In this paper, we present a novel method for modeling multiple time series annotations over a continuous variable that computes the ground truth by modeling annotator specific distortions. We condition the ground truth on a set of features extracted from the data and further assume that the annotators provide their ratings as modification of the ground truth, with each annotator having specific distortion tendencies. We train the model using an Expectation-Maximization based algorithm and evaluate it on a study involving natural interaction between a child and a psychologist, to predict confidence ratings of the children's smiles. We compare and analyze the model against two baselines where: (i) the ground truth in considered to be framewise mean of ratings from various annotators and, (ii) each annotator is assumed to bear a distinct time delay in annotation and their annotations are aligned before computing the framewise mean.

Growth rates of three geographically separated strains of the ichthyotoxic Prymnesium parvum (Prymnesiophyceae) in response to six different pH levels

NASA Astrophysics Data System (ADS)

Lysgaard, Maria L.; Eckford-Soper, Lisa; Daugbjerg, Niels

2018-05-01

Continued anthropogenic carbon emissions are expected to cause a decline in global average pH of the oceans to a projected value of 7.8 by the end of the century. Understanding how harmful algal bloom (HAB) species will respond to lowered pH levels will be important when predicting future HAB events and their ecological consequences. In this study, we examined how manipulated pH levels affected the growth rate of three strains of Prymnesium parvum from North America, Denmark and Japan. Triplicate strains were grown under pH conditions ranging from 6.6 to 9.1 to simulate plausible future levels. Different tolerances were evident for all strains. Significantly higher growth rates were observed at pH 6.6-8.1 compared to growth rates at pH 8.6-9.1 and a lower pH limit was not observed. The Japanese strain (NIES-1017) had the highest maximum growth rate of 0.39 divisions day-1 at pH 6.6 but a low tolerance (0.22 divisions day-1) to high levels (pH 9.1) with growth declining markedly after pH 7.6. The Danish (SCCAP K-0081) and North American (UTEX LB 2797) strains had maximum growth rates of 0.26 and 0.35 divisions day-1, respectively between pH 6.6-8.1. Compared to the other two strains the Danish strain had a statistically lower growth rate across all pH treatments. Strain differences were either attributed to their provenance or the length of time the strain had been in culture.

Intereruptive deformation at Three Sisters volcano, Oregon, USA: a strategy for traking volume changes through coupled hydraulic-viscoelastic modeling

NASA Astrophysics Data System (ADS)

Charco, M.; Rodriguez Molina, S.; Gonzalez, P. J.; Negredo, A. M.; Poland, M. P.; Schmidt, D. A.

2017-12-01

The Three Sisters volcanic region Oregon (USA) is one of the most active volcanic areas in the Cascade Range and is densely populated with eruptive vents. An extensive area just west of South Sister volcano has been actively uplifting since about 1998. InSAR data from 1992 through 2001 showed an uplift rate in the area of 3-4 cm/yr. Then the deformation rate considerably decreased between 2004 and 2006 as shown by both InSAR and continuous GPS measurements. Once magmatic system geometry and location are determined, a linear inversion of all GPS and InSAR data available is performed in order to estimate the volume changes of the source along the analyzed time interval. For doing so, we applied a technique based on the Truncated Singular Value Decomposition (TSVD) of the Green's function matrix representing the linear inversion. Here, we develop a strategy to provide a cut-off for truncation removing the smallest singular values without too much loose of data resolution against the stability of the method. Furthermore, the strategy will give us a quantification of the uncertainty of the volume change time series. The strength of the methodology resides in allowing the joint inversion of InSAR measurements from multiple tracks with different look angles and three component GPS measurements from multiple sites.Finally, we analyze the temporal behavior of the source volume changes using a new analytical model that describes the process of injecting magma into a reservoir surrounded by a viscoelastic shell. This dynamic model is based on Hagen-Poiseuille flow through a vertical conduit that leads to an increase in pressure within a spherical reservoir and time-dependent surface deformation. The volume time series are compared to predictions from the dynamic model to constrain model parameters, namely characteristic Poiseuille and Maxwell time scales, inlet and outlet injection pressure, and source and shell geometries. The modeling approach used here could be used to develop a mathematically rigorous strategy for including time-series deformation data in the interpretation of volcanic unrest.

Cost-effectiveness of treatment strategies in women with PCOS who do not conceive after six cycles of clomiphene citrate.

PubMed

Moolenaar, Lobke M; Nahuis, Marleen J; Hompes, Peter G; van der Veen, Fulco; Mol, Ben Willem J

2014-05-01

This study evaluated the cost-effectiveness of treatments for women with polycystic ovary syndrome (PCOS) who ovulate on clomiphene citrate but do not conceive after six cycles. A decision-analytic framework was developed for six scenarios: (1) three cycles of IVF; (2) continuation of clomiphene citrate for six cycles, followed by three cycles of IVF in case of no birth; (3) six cycles of gonadotrophins and three cycles of IVF; (4) 12 cycles of gonadotrophins and three cycles of IVF; (5) continuation of clomiphene citrate for six cycles, six cycles of gonadotrophins and three cycles of IVF; (6) continuation of clomiphene citrate for six cycles, 12 cycles of gonadotrophins and three cycles of IVF. Two-year cumulative birth rates were 58%, 74%, 89%, 97%, 93% and 98% and costs per couple were € 9518, € 7530, € 9711, € 9764, € 7651 and € 7684 for scenarios 1-6, respectively. Scenario 2 was the lowest cost option. The extra cost for at least one live birth in scenario 5 was € 629 and in scenario 6 € 630. In these subjects, continuation of treatment for six cycles of clomiphene citrate, 6 or 12 cycles of gonadotrophins and IVF is potentially cost-effective. These results should be confirmed in a randomized clinical trial. Copyright © 2014 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.

40 CFR 63.9920 - What are my continuous monitoring requirements?

Code of Federal Regulations, 2012 CFR

2012-07-01

... scrubber subject to the operating limits for pressure drop and scrubber water flow rates in § 63.9890(b), you must at all times monitor the hourly average pressure drop and liquid flow rate using a CPMS...

40 CFR 63.9920 - What are my continuous monitoring requirements?

Code of Federal Regulations, 2013 CFR

2013-07-01

... scrubber subject to the operating limits for pressure drop and scrubber water flow rates in § 63.9890(b), you must at all times monitor the hourly average pressure drop and liquid flow rate using a CPMS...

40 CFR 63.9920 - What are my continuous monitoring requirements?

Code of Federal Regulations, 2010 CFR

2010-07-01

... scrubber subject to the operating limits for pressure drop and scrubber water flow rates in § 63.9890(b), you must at all times monitor the hourly average pressure drop and liquid flow rate using a CPMS...

Effect of loading rate on the monotonic tensile behavior of a continuous-fiber-reinforced glass-ceramic matrix composite

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

Soerensen, B.F.; Holmes, J.W.

The stress-strain behavior of a continuous-fiber-reinforced ceramic matrix composite has been measured over a wide range of loading rates (0.01 to 500 MPa/s). It was found that the loading rate has a strong effect on almost every feature of the stress-strain curve: the proportionality stress, the composite strength and failure strain increase with increasing loading rate. The microstructural damage varies also with the loading rate; with increasing loading rate, the average matrix crack spacing increases and the average fiber pullout length decreases. Using simple models, it is suggested that these phenomena are caused partly by time-dependent matrix cracking (due tomore » stress corrosion) and partly by an increasing interfacial shear stress with loading rate.« less

Models for integrated pest control and their biological implications.

PubMed

Tang, Sanyi; Cheke, Robert A

2008-09-01

Successful integrated pest management (IPM) control programmes depend on many factors which include host-parasitoid ratios, starting densities, timings of parasitoid releases, dosages and timings of insecticide applications and levels of host-feeding and parasitism. Mathematical models can help us to clarify and predict the effects of such factors on the stability of host-parasitoid systems, which we illustrate here by extending the classical continuous and discrete host-parasitoid models to include an IPM control programme. The results indicate that one of three control methods can maintain the host level below the economic threshold (ET) in relation to different ET levels, initial densities of host and parasitoid populations and host-parasitoid ratios. The effects of host intrinsic growth rate and parasitoid searching efficiency on host mean outbreak period can be calculated numerically from the models presented. The instantaneous pest killing rate of an insecticide application is also estimated from the models. The results imply that the modelling methods described can help in the design of appropriate control strategies and assist management decision-making. The results also indicate that a high initial density of parasitoids (such as in inundative releases) and high parasitoid inter-generational survival rates will lead to more frequent host outbreaks and, therefore, greater economic damage. The biological implications of this counter intuitive result are discussed.

EMG biofeedback: the effects of CRF, FR, VR, FI, and VI schedules of reinforcement on the acquisition and extinction of increases in forearm muscle tension.

PubMed

Cohen, S L; Richardson, J; Klebez, J; Febbo, S; Tucker, D

2001-09-01

Biofeedback was used to increase forearm-muscle tension. Feedback was delivered under continuous reinforcement (CRF), variable interval (VI), fixed interval (FI), variable ratio (VR), and fixed ratio (FR) schedules of reinforcement when college students increased their muscle tension (electromyograph, EMG) above a high threshold. There were three daily sessions of feedback, and Session 3 was immediately followed by a session without feedback (extinction). The CRF schedule resulted in the highest EMG, closely followed by the FR and VR schedules, and the lowest EMG scores were produced by the FI and VI schedules. Similarly, the CRF schedule resulted in the greatest amount of time-above-threshold and the VI and FI schedules produced the lowest time-above-threshold. The highest response rates were generated by the FR schedule, followed by the VR schedule. The CRF schedule produced relatively low response rates, comparable to the rates under the VI and FI schedules. Some of the data are consistent with the partial-reinforcement-extinction effect. The present data suggest that different schedules of feedback should be considered in muscle-strengthening-contexts such as during the rehabilitation of muscles following brain damage or peripheral nervous-system injury.

Hospitalization rates among dialysis patients during Hurricane Katrina.

PubMed

Howard, David; Zhang, Rebecca; Huang, Yijian; Kutner, Nancy

2012-08-01

Dialysis centers struggled to maintain continuity of care for dialysis patients during and immediately following Hurricane Katrina's landfall on the US Gulf Coast in August 2005. However, the impact on patient health and service use is unclear. The impact of Hurricane Katrina on hospitalization rates among dialysis patients was estimated. Data from the United States Renal Data System were used to identify patients receiving dialysis from January 1, 2001 through August 29, 2005 at clinics that experienced service disruptions during Hurricane Katrina. A repeated events duration model was used with a time-varying Hurricane Katrina indicator to estimate trends in hospitalization rates. Trends were estimated separately by cause: surgical hospitalizations, medical, non-renal-related hospitalizations, and renal-related hospitalizations. The rate ratio for all-cause hospitalization associated with the time-varying Hurricane Katrina indicator was 1.16 (95% CI, 1.05-1.29; P = .004). The ratios for cause-specific hospitalization were: surgery, 0.84 (95% CI, 0.68-1.04; P = .11); renal-related admissions, 2.53 (95% CI, 2.09-3.06); P < .001), and medical non-renal related, 1.04 (95% CI, 0.89-1.20; P = .63). The estimated number of excess renal-related hospital admissions attributable to Katrina was 140, representing approximately three percent of dialysis patients at the affected clinics. Hospitalization rates among dialysis patients increased in the month following the Hurricane Katrina landfall, suggesting that providers and patients were not adequately prepared for large-scale disasters.

Attentional modulation of desensitization to odor.

PubMed

Fallon, Nicholas; Giesbrecht, Timo; Stancak, Andrej

2018-05-22

Subjective and behavioral responsiveness to odor diminishes during prolonged exposure. The precise mechanisms underlying olfactory desensitization are not fully understood, but previous studies indicate that the phenomenon may be modulated by central-cognitive processes. The present study investigated the effect of attention on perceived intensity during exposure to a pleasant odor. A within-subjects design was utilized with 19 participants attending 2 sessions. During each session, participants continuously rated their perceived intensity of a 10-minute exposure to a pleasant fragrance administered using an olfactometer. An auditory oddball task was implemented to manipulate the focus of attention in each session. Participants were instructed to either direct their attention toward the sounds, but still to rate odor, or to focus entirely on rating the odor. Analysis revealed three 50-second time windows with significantly lower mean intensity ratings during the distraction condition. Curve fitting of the data disclosed a linear function of desensitization in the focused attention condition compared with an exponential decay function during distraction condition, indicating an increased rate of initial desensitization when attention is distracted away from the odor. In the focused-attention condition, perceived intensity demonstrated a regular pattern of odor sensitivity occurring at approximately 1-2 minutes intervals following initial desensitization. Spectral analysis of low-frequency oscillations confirmed the presence of augmented spectral power in this frequency range during focused relative to distracted conditions. The findings demonstrate for the first time modulation of odor desensitization specifically by attentional factors, exemplifying the relevance of top-down control for ongoing perception of odor.

An Assessment of Meyer and Allen's (1991) Three-Component Model of Organizational Commitment and Turnover Intentions.

ERIC Educational Resources Information Center

Jaros, Stephen J.

1997-01-01

Data from 158 part-time graduate students employed full time and 160 aerospace engineers were used to test a model of organizational commitment. Contrary to expectations, the three components of commitment (affective, normative, continuance) differed in their effects on intention to quit. Affective commitment had a significantly stronger…

The Times They Are a-Changin': Time for a Major Emphasis on the Three LS of Lifelong Learning at Canadian Universities

ERIC Educational Resources Information Center

Middleton, Alan

2011-01-01

This article contends that university continuing education is in need of a dramatic repositioning in the minds and wallets of most university administrations. In order to respond both to a developed economy's need for the continuous upgrading of skills and knowledge and to universities' needs for new funding sources, the provision of lifelong…

Head-up transition behavior of pilots during simulated low-visibility approaches

NASA Technical Reports Server (NTRS)

Haines, R. F.

1980-01-01

Each of 13 commercial pilots from four airlines flew a total of 108 manual flight director approaches in a moving base simulation of a medium-sized turbojet (95,000 lb gross weight) which had a day and night Redifon external scene. Three levels of runway visual range (RVR) (1,600; 2,400; and greater than 8,000 ft), three wind-shear profiles, nine ceiling heights, and continuous and intermittent visibility after initial breakout were tested. The results indicated that: (1) mean decision time ranged from 2 to 4.6 sec for ceilings under 380 ft across the three RVR conditions; (2) mean vertical distance traveled during the visual-cue assessment period was a relatively constant proportion below the existing ceiling; (3) a significant three way interaction in mean decision time between wind shear, day-night, and ceiling RVR variables occurred; (4) mean number of head-up transitions to VFR conditions after breakout ranged from 4.6 to 13.4 and increased as a function of ceiling and severity of wind shear; the typical duration of fixation out the window was 1.5 sec; and (5) subjective pilot ratings of controllability and precision of control as well as amount of skill, attention, or effort required to make the landing were influenced significantly by the wind shear, night conditions, and low breakout ceiling conditions.

Patient–doctor continuity and diagnosis of cancer: electronic medical records study in general practice

PubMed Central

Ridd, Matthew J; Ferreira, Diana L Santos; Montgomery, Alan A; Salisbury, Chris; Hamilton, William

2015-01-01

Background Continuity of care may affect the diagnostic process in cancer but there is little research. Aim To estimate associations between patient–doctor continuity and time to diagnosis and referral of three common cancers. Design and setting Retrospective cohort study in general practices in England. Method This study used data from the General Practice Research Database for patients aged ≥40 years with a diagnosis of breast, colorectal, or lung cancer. Relevant cancer symptoms or signs were identified up to 12 months before diagnosis. Patient–doctor continuity (fraction-of-care index adjusted for number of consultations) was calculated up to 24 months before diagnosis. Time ratios (TRs) were estimated using accelerated failure time regression models. Results Patient–doctor continuity in the 24 months before diagnosis was associated with a slightly later diagnosis of colorectal (time ratio [TR] 1.01, 95% confidence interval [CI] =1.01 to 1.02) but not breast (TR = 1.00, 0.99 to 1.01) or lung cancer (TR = 1.00, 0.99 to 1.00). Secondary analyses suggested that for colorectal and lung cancer, continuity of doctor before the index consultation was associated with a later diagnosis but continuity after the index consultation was associated with an earlier diagnosis, with no such effects for breast cancer. For all three cancers, most of the delay to diagnosis occurred after referral. Conclusion Any effect for patient–doctor continuity appears to be small. Future studies should compare investigations, referrals, and diagnoses in patients with and without cancer who present with possible cancer symptoms or signs; and focus on ‘difficult to diagnose’ types of cancer. PMID:25918335

Ground System for Solar Dynamics Observatory (SDO) Mission

NASA Technical Reports Server (NTRS)

Tann, Hun K.; Silva, Christopher J.; Pages, Raymond J.

2005-01-01

NASA s Goddard Space Flight Center (GSFC) has recently completed its Critical Design Review (CDR) of a new dual Ka and S-band ground system for the Solar Dynamics Observatory (SDO) Mission. SDO, the flagship mission under the new Living with a Star Program Office, is one of GSFC s most recent large-scale in-house missions. The observatory is scheduled for launch in August 2008 from the Kennedy Space Center aboard an Atlas-5 expendable launch vehicle. Unique to this mission is an extremely challenging science data capture requirement. The mission is required to capture 99.99% of available science over 95% of all observation opportunities. Due to the continuous, high volume (150 Mbps) science data rate, no on-board storage of science data will be implemented on this mission. With the observatory placed in a geo-synchronous orbit at 36,000 kilometers within view of dedicated ground stations, the ground system will in effect implement a "real-time" science data pipeline with appropriate data accounting, data storage, data distribution, data recovery, and automated system failure detection and correction to keep the science data flowing continuously to three separate Science Operations Centers (SOCs). Data storage rates of approx. 45 Tera-bytes per month are expected. The Mission Operations Center (MOC) will be based at GSFC and is designed to be highly automated. Three SOCs will share in the observatory operations, each operating their own instrument. Remote operations of a multi-antenna ground station in White Sands, New Mexico from the MOC is part of the design baseline.

Affective Forecasting and Self-Rated Symptoms of Depression, Anxiety, and Hypomania: Evidence for a Dysphoric Forecasting Bias

PubMed Central

Hoerger, Michael; Quirk, Stuart W.; Chapman, Benjamin P.; Duberstein, Paul R.

2011-01-01

Emerging research has examined individual differences in affective forecasting; however, we are aware of no published study to date linking psychopathology symptoms to affective forecasting problems. Pitting cognitive theory against depressive realism theory, we examined whether dysphoria was associated with negatively biased affective forecasts or greater accuracy. Participants (n = 325) supplied predicted and actual emotional reactions for three days surrounding an emotionally-evocative relational event, Valentine’s Day. Predictions were made a month prior to the holiday. Consistent with cognitive theory, we found evidence for a dysphoric forecasting bias – the tendency of individuals in dysphoric states to overpredict negative emotional reactions to future events. The dysphoric forecasting bias was robust across ratings of positive and negative affect, forecasts for pleasant and unpleasant scenarios, continuous and categorical operationalizations of dysphoria, and three time points of observation. Similar biases were not observed in analyses examining the independent effects of anxiety and hypomania. Findings provide empirical evidence for the long assumed influence of depressive symptoms on future expectations. The present investigation has implications for affective forecasting studies examining information processing constructs, decision making, and broader domains of psychopathology. PMID:22397734

Affective forecasting and self-rated symptoms of depression, anxiety, and hypomania: evidence for a dysphoric forecasting bias.

PubMed

Hoerger, Michael; Quirk, Stuart W; Chapman, Benjamin P; Duberstein, Paul R

2012-01-01

Emerging research has examined individual differences in affective forecasting; however, we are aware of no published study to date linking psychopathology symptoms to affective forecasting problems. Pitting cognitive theory against depressive realism theory, we examined whether dysphoria was associated with negatively biased affective forecasts or greater accuracy. Participants (n=325) supplied predicted and actual emotional reactions for three days surrounding an emotionally evocative relational event, Valentine's Day. Predictions were made a month prior to the holiday. Consistent with cognitive theory, we found evidence for a dysphoric forecasting bias-the tendency of individuals in dysphoric states to overpredict negative emotional reactions to future events. The dysphoric forecasting bias was robust across ratings of positive and negative affect, forecasts for pleasant and unpleasant scenarios, continuous and categorical operationalisations of dysphoria, and three time points of observation. Similar biases were not observed in analyses examining the independent effects of anxiety and hypomania. Findings provide empirical evidence for the long-assumed influence of depressive symptoms on future expectations. The present investigation has implications for affective forecasting studies examining information-processing constructs, decision making, and broader domains of psychopathology.

Multiple Days of Heat Exposure on Firefighters' Work Performance and Physiology.

PubMed

Larsen, Brianna; Snow, Rod; Vincent, Grace; Tran, Jacqueline; Wolkow, Alexander; Aisbett, Brad

2015-01-01

This study assessed the accumulated effect of ambient heat on the performance of, and physiological and perceptual responses to, intermittent, simulated wildfire fighting tasks over three consecutive days. Firefighters (n = 36) were matched and allocated to either the CON (19°C) or HOT (33°C) condition. They performed three days of intermittent, self-paced simulated firefighting work, interspersed with physiological testing. Task repetitions were counted (and converted to distance or area) to determine work performance. Participants were asked to rate their perceived exertion and thermal sensation after each task. Heart rate, core temperature (Tc), and skin temperature (Tsk) were recorded continuously throughout the simulation. Fluids were consumed ad libitum. Urine volume was measured throughout, and urine specific gravity (USG) analysed, to estimate hydration. All food and fluid consumption was recorded. There was no difference in work output between experimental conditions. However, significant variation in performance responses between individuals was observed. All measures of thermal stress were elevated in the HOT, with core and skin temperature reaching, on average, 0.24 ± 0.08°C and 2.81 ± 0.20°C higher than the CON group. Participants' doubled their fluid intake in the HOT condition, and this was reflected in the USG scores, where the HOT participants reported significantly lower values. Heart rate was comparable between conditions at nearly all time points, however the peak heart rate reached each circuit was 7 ± 3% higher in the CON trial. Likewise, RPE was slightly elevated in the CON trial for the majority of tasks. Participants' work output was comparable between the CON and HOT conditions, however the performance change over time varied significantly between individuals. It is likely that the increased fluid replacement in the heat, in concert with frequent rest breaks and task rotation, assisted with the regulation of physiological responses (e.g., heart rate, core temperature).

The effect of chewing gum's flavor on salivary flow rate and pH.

PubMed

Karami-Nogourani, Maryam; Kowsari-Isfahan, Raha; Hosseini-Beheshti, Mozhgan

2011-12-01

Chewing sugar-free gums is a convenient way to increase salivary flow. Salivary flow increases in response to both gustatory (taste) and mechanical (chewing) stimuli, and chewing gum can provide both of these stimuli. The aim of this study was to compare the effect of five different flavors of sugar-free chewing gum on the salivary flow rate (SFR) and pH. Fifteen dental students volunteered at the same time on six consecutive days, to collect one minute unstimulated saliva. After five minutes, while some volunteers continued to collect only unstimulated saliva, the others asked to start chewing one of the five flavored gums randomly. The flavors were spearmint, cinnamon, watermelon, strawberry, and apple. The whole saliva was collected over time periods of 0 - 1, 1 - 3, and 3 - 6 minutes, and the SFR and pH were also measured. The data were subjected to pair t-test, repeated-measures analysis of variance, and Duncan tests. Compared to the unstimulated rate, all five different flavored gums significantly increased the SFR within six minutes. Although the flow rate peaked during the first minute of stimulation with all five products, it reduced gradually, but still remained above the unstimulated saliva, after six minutes. In the first minute, the strawberry-flavored gums showed the highest weight, yet, it only induced a significantly higher SFR compared to the cinnamon-flavored gums. During one to three minutes, strawberry and apple-flavored gums showed significantly higher SFR, respectively, compared to cinnamon-flavored gums. There were no significant differences in the flow rates elicited by each flavored gum through the three-to-six minute interval, although the spearmint-flavored gums induced slightly higher SFR. Only the spearmint and cinnamon-flavored gum significantly increased the salivary pH. Gum flavor can affect the SFR and special flavors may be advised for different individuals according to their oral conditions.

Multiple Days of Heat Exposure on Firefighters’ Work Performance and Physiology

PubMed Central

Larsen, Brianna; Snow, Rod; Vincent, Grace; Tran, Jacqueline; Wolkow, Alexander; Aisbett, Brad

2015-01-01

This study assessed the accumulated effect of ambient heat on the performance of, and physiological and perceptual responses to, intermittent, simulated wildfire fighting tasks over three consecutive days. Firefighters (n = 36) were matched and allocated to either the CON (19°C) or HOT (33°C) condition. They performed three days of intermittent, self-paced simulated firefighting work, interspersed with physiological testing. Task repetitions were counted (and converted to distance or area) to determine work performance. Participants were asked to rate their perceived exertion and thermal sensation after each task. Heart rate, core temperature (Tc), and skin temperature (Tsk) were recorded continuously throughout the simulation. Fluids were consumed ad libitum. Urine volume was measured throughout, and urine specific gravity (USG) analysed, to estimate hydration. All food and fluid consumption was recorded. There was no difference in work output between experimental conditions. However, significant variation in performance responses between individuals was observed. All measures of thermal stress were elevated in the HOT, with core and skin temperature reaching, on average, 0.24 ± 0.08°C and 2.81 ± 0.20°C higher than the CON group. Participants’ doubled their fluid intake in the HOT condition, and this was reflected in the USG scores, where the HOT participants reported significantly lower values. Heart rate was comparable between conditions at nearly all time points, however the peak heart rate reached each circuit was 7 ± 3% higher in the CON trial. Likewise, RPE was slightly elevated in the CON trial for the majority of tasks. Participants’ work output was comparable between the CON and HOT conditions, however the performance change over time varied significantly between individuals. It is likely that the increased fluid replacement in the heat, in concert with frequent rest breaks and task rotation, assisted with the regulation of physiological responses (e.g., heart rate, core temperature). PMID:26379284

WTP Waste Feed Qualification: Hydrogen Generation Rate Measurement Apparatus Testing Report

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

Stone, M. E.; Newell, J. D.; Smith, T. E.

The generation rate of hydrogen gas in the Hanford tank waste will be measured during the qualification of the staged tank waste for processing in the Hanford Tank Waste Treatment and Immobilization Plant. Based on a review of past practices in measurement of the hydrogen generation, an apparatus to perform this measurement has been designed and tested for use during waste feed qualification. The hydrogen generation rate measurement apparatus (HGRMA) described in this document utilized a 100 milliliter sample in a continuously-purged, continuously-stirred vessel, with measurement of hydrogen concentration in the vent gas. The vessel and lid had a combinedmore » 220 milliliters of headspace. The vent gas system included a small condenser to prevent excessive evaporative losses from the sample during the test, as well as a demister and filter to prevent particle migration from the sample to the gas chromatography system. The gas chromatograph was an on line automated instrument with a large-volume sample-injection system to allow measurement of very low hydrogen concentrations. This instrument automatically sampled the vent gas from the hydrogen generation rate measurement apparatus every five minutes and performed data regression in real time. The fabrication of the hydrogen generation rate measurement apparatus was in accordance with twenty three (23) design requirements documented in the conceptual design package, as well as seven (7) required developmental activities documented in the task plan associated with this work scope. The HGRMA was initially tested for proof of concept with physical simulants, and a remote demonstration of the system was performed in the Savannah River National Laboratory Shielded Cells Mockup Facility. Final verification testing was performed using non-radioactive simulants of the Hanford tank waste. Three different simulants were tested to bound the expected rheological properties expected during waste feed qualification testing. These simulants were tested at different temperatures using purge gas spiked with varying amounts of hydrogen to provide verification that the system could accurately measure the hydrogen in the vent gas at steady state.« less

A Statistical Study on VLF Subionospheric Perturbations Associated with Major Earthquakes: A View from Focal Mechanism

NASA Astrophysics Data System (ADS)

Kawano, T.; Tatsuta, K.; Hobara, Y.

2015-12-01

Continuous monitoring of signal amplitudes of worldwide VLF transmitters is a powerful tool to study the lower ionospheric condition. Although, lower ionospheric perturbations prior to some of the major earthquakes have been reported for years, their occurrence and coupling mechanism between the ground and overlaying ionosphere prior to the earthquakes are not clear yet. In this paper, we carried out a statistical analysis based on the nighttime averaged signal amplitude data from the UEC's VLF/LF transmitter observation network. Two hundred forty three earthquakes were occurred within the 5th Fresnel zone of transmitter-receiver paths around Japan during the time period of 2007 to 2012. These earthquakes were characterized into three different groups based on the Centroid-Moment-Tensor (CMT) solution such as reverse fault type, normal fault type and stress slip type. The ionospheric anomaly was identified by a large change in the VLF/LF amplitude during nighttime. As a result, we found the ionospheric perturbations associated with both ground and sea earthquakes. Remarkably, the reverse fault type earthquakes have the highest occurrence rate of ionospheric perturbation among the three types both for sea (41%) and ground events (61%). The occurrence rates for normal type fault are 35% and 56% for sea and ground earthquakes respectively and the same for stress slip type are 39% and 20% for sea and ground earthquakes respectively. In both cases the occurrence rates are smaller than the reverse fault type. The clear difference of occurrence rate of the ionospheric perturbations may indicate that the coupling efficiency of seismic activity into the overlaying ionosphere is controlled by the pressure in the earth's crust. This gives us further physical insight of Lithosphere-Atmosphere-Ionosphere (LAI) coupling processes.

Identification of Psychological Stresses for Astronauts and Cosmonauts

NASA Astrophysics Data System (ADS)

Marsh, Melinda

As humans continue to explore and expand in the solar system, psychological problems brought about by high stress of living in the space environment will continue to increase. Unfortunately, due to many reasons, including relative difficulties with gaining access to astronauts and cosmonauts and to gather psychological data from them regarding stressors, this area is not very well known and discussed. Five astronauts and cosmonauts from three space agencies: ESA, RSA, and JAXA were unoffi- cially surveyed regarding their experiences with ten general categories of psychological stressors as well as eight subcategories of interpersonal conflict stressors accepted in space related community of psychologists. The two subjects in space for longer periods of time reported more stressors and were likely to rate stressors as having a greater effect on the chance of mission failure. Shorter duration flyers reported nearly all general stressors were likely to increase in the event of a longer duration space flight. With the increased interest in long duration spaceflight, psychological stressors are more likely to affect mission success.

Utility of Sleep Stage Transitions in Assessing Sleep Continuity

PubMed Central

Laffan, Alison; Caffo, Brian; Swihart, Bruce J.; Punjabi, Naresh M.

2010-01-01

Study Objectives: Sleep continuity is commonly assessed with polysomnographic measures such as sleep efficiency, sleep stage percentages, and the arousal index. The aim of this study was to examine whether the transition rate between different sleep stages could be used as an index of sleep continuity to predict self-reported sleep quality independent of other commonly used metrics. Design and Setting: Analysis of the Sleep Heart Health Study polysomnographic data. Participants: A community cohort. Measurements and Results: Sleep recordings on 5,684 participants were deemed to be of sufficient quality to allow visual scoring of NREM and REM sleep. For each participant, we tabulated the frequency of transitions between wake, NREM sleep, and REM sleep. An overall transition rate was determined as the number of all transitions per hour sleep. Stage-specific transition rates between wake, NREM sleep, and REM sleep were also determined. A 5-point Likert scale was used to assess the subjective experience of restless and light sleep the morning after the sleep study. Multivariable regression models showed that a high overall sleep stage transition rate was associated with restless and light sleep independent of several covariates including total sleep time, percentages of sleep stages, wake time after sleep onset, and the arousal index. Compared to the lowest quartile of the overall transition rate (< 7.76 events/h), the odds ratios for restless sleep were 1.27, 1.42, and 1.38, for the second (7.77–10.10 events/h), third (10.11–13.34 events/h), and fourth (≥ 13.35 events/h) quartiles, respectively. Analysis of stage-specific transition rates showed that transitions between wake and NREM sleep were also independently associated with restless and light sleep. Conclusions: Assessing overall and stage-specific transition rates provides a complementary approach for assessing sleep continuity. Incorporating such measures, along with conventional metrics, could yield useful insights into the significance of sleep continuity for clinical outcomes. Citation: Laffan A; Caffo B; Swihart BJ; Punjabi NM. Utility of sleep stage transitions in assessing sleep continuity. SLEEP 2010;33(12):1681-1686. PMID:21120130

Arbuscular mycorrhizal fungal communities in the rhizosphere of a continuous cropping soybean system at the seedling stage.

PubMed

Cui, Jiaqi; Bai, Li; Liu, Xiaorui; Jie, Weiguang; Cai, Baiyan

Arbuscular mycorrhizae (AM) fungi play a crucial role in the growth of soybean; however, the planting system employed is thought to have an effect on AM fungal communities in the rhizosphere. This study was performed to explore the influence of continuous soybean cropping on the diversity of Arbuscular mycorrhizal (AM) fungi, and to identify the dominant AM fungus during the seedling stage. Three soybean cultivars were planted under two and three years continuous cropping, respectively. The diversity of AM fungi in the rhizosphere soil at the seedling stage was subsequently analyzed using polymerase chain reaction (PCR)-denaturing gradient gel electrophoresis (DGGE). The results showed that an increase in cropping years improved the colonization rate of AM in all three soybean cultivars. Moreover, the dominant species were found to be Funneliformis mosseae and Glomus species. The results of cluster analysis further confirmed that the number of years of continuous cropping significantly affected the composition of rhizospheric AM fungal communities in different soybean cultivars. Copyright © 2017 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.

A dose-response study of dexmedetomidine administered as the primary sedative in infants following open heart surgery.

PubMed

Su, Felice; Nicolson, Susan C; Zuppa, Athena F

2013-06-01

To evaluate the dose-response relationship of dexmedetomidine in infants with congenital heart disease postoperative from open heart surgery. Prospective open-label dose-escalation pharmacokinetic-pharmacodynamic study. Tertiary pediatric cardiac ICU. Thirty-six evaluable infants, 1-24 months old, postoperative from open heart surgery requiring mechanical ventilation. Cohorts of 12 infants were enrolled sequentially to one of the three IV loading doses of dexmedetomidine (0.35, 0.7, and 1 mcg/kg) over 10 minutes followed by respective continuous infusions (0.25, 0.5, and 0.75 mcg/kg/hr) for up to 24 hours. Dexmedetomidine plasma concentrations were obtained at timed intervals during and following discontinuation of infusion. Pharmacodynamic variables evaluated included sedation scores, supplemental sedation and analgesia medication administration, time to tracheal extubation, respiratory function, and hemodynamic parameters. Infants achieved a deeper sedation measured by the University of Michigan Sedation Scale score (2.6 vs 1) despite requiring minimal supplemental sedation (0 unit doses/hr) and fewer analgesic medications (0.07 vs 0.15 unit doses/hr) while receiving dexmedetomidine compared with the 12-hour follow-up period. Thirty-one patients were successfully extubated while receiving the dexmedetomidine infusion. Only one patient remained intubated due to oversedation during the infusion. While receiving dexmedetomidine, there was a decrease in heart rate compared with baseline, 132 versus 161 bpm, but there was an increase in heart rate compared with postinfusion values, 132 versus 128 bpm. There was no statistically or clinically significant change in mean arterial blood pressure. Dexmedetomidine administration in infants following open heart surgery can provide improved sedation with reduction in supplemental medication requirements, leading to successful extubation while receiving a continuous infusion. The postoperative hemodynamic changes that occur in infants postoperative from open heart surgery are multifactorial. Although dexmedetomidine may play a role in decreasing heart rate immediately postoperative, the changes were not clinically significant and did not fall below postinfusion heart rates.

Batch and fixed-bed biosorption of Cd(II) from aqueous solution using immobilized Pleurotus ostreatus spent substrate.

PubMed

Jin, Yu; Teng, Chunying; Yu, Sumei; Song, Tao; Dong, Liying; Liang, Jinsong; Bai, Xin; Liu, Xuesheng; Hu, Xiaojing; Qu, Juanjuan

2018-01-01

To prevent the blockage in a continuous fix-bed system, Pleurotus Ostreatus spent substrate (POSS), a composite agricultural waste, was immobilized into granular adsorbents (IPOSS) with polymeric matrix, and used to remove Cd(II) from synthetic wastewater in batch experiment as well as in continuous fixed-bed column system. In batch experiment, higher pH, temperature and Cd(II) initial concentration were conducive to a higher biosorption capacity, and the maximum biosorption capacity reached up to 87.2 mg/g at Cd(II) initial concentration of 200 mg/L, pH 6 and 25 °C. The biosorption of Cd(II) onto IPOSS followed the Langmuir isotherm model with the maximum adsorption capacity(q max ) of 100 mg/g. The biosorption was an endothermic reaction and a spontaneous process based on positive value of ΔH 0 and negative value of ΔG 0 . In fixed-bed column system, higher bed depth, lower flow rate and influent Cd(II) concentration led to a longer breakthrough and exhaustion time, and the best performance (equilibrium uptake (q e ) of 14.4 mg, breakthrough time at 31 h and exhaustion time at 78 h) was achieved at a bed depth of 110 cm, a flow rate of 1.2 L/h and an influent concentration of 100 mg/L. Furthermore, regeneration experiment revealed a good reusability of IPOSS with 0.1 M HNO 3 as eluting agent during three cycles of adsorption and desorption. Cd(II) biosorption onto IPOSS mainly relied on a chemical process including ion exchange and complexation or coordination revealed by SEM-EDX, FTIR and XRD analysis. Copyright © 2017. Published by Elsevier Ltd.

20 CFR 10.216 - How is the pay rate for COP calculated?

Code of Federal Regulations, 2014 CFR

2014-04-01

... 20 Employees' Benefits 1 2014-04-01 2012-04-01 true How is the pay rate for COP calculated? 10.216... AMENDED Continuation of Pay Calculation of Cop § 10.216 How is the pay rate for COP calculated? The employer shall calculate COP using the period of time and the weekly pay rate. (a) The pay rate for COP...

20 CFR 10.216 - How is the pay rate for COP calculated?

Code of Federal Regulations, 2013 CFR

2013-04-01

... 20 Employees' Benefits 1 2013-04-01 2012-04-01 true How is the pay rate for COP calculated? 10.216... AMENDED Continuation of Pay Calculation of Cop § 10.216 How is the pay rate for COP calculated? The employer shall calculate COP using the period of time and the weekly pay rate. (a) The pay rate for COP...

Three-Dimensional Bi-Continuous Nanoporous Gold/Nickel Foam Supported MnO2 for High Performance Supercapacitors.

PubMed

Zhao, Jie; Zou, Xilai; Sun, Peng; Cui, Guofeng

2017-12-19

A three-dimensional bi-continuous nanoporous gold (NPG)/nickel foam is developed though the electrodeposition of a gold-tin alloy on Ni foam and subsequent chemical dealloying of tin. The newly-designed 3D metal structure is used to anchor MnO 2 nanosheets for high-performance supercapacitors. The formed ternary composite electrodes exhibit significantly-enhanced capacitance performance, rate capability, and excellent cycling stability. A specific capacitance of 442 Fg -1 is achieved at a scan rate of 5 mV s -1 and a relatively high mass loading of 865 μg cm -2 . After 2500 cycles, only a 1% decay is found at a scan rate of 50 mV s -1 . A high power density of 3513 W kg -1 and an energy density of 25.73 Wh kg -1 are realized for potential energy storage devices. The results demonstrate that the NPG/nickel foam hybrid structure significantly improves the dispersibility of MnO 2 and makes it promising for practical energy storage applications.

Shape-Controlled Synthesis of Hybrid Nanomaterials via Three-Dimensional Hydrodynamic Focusing

PubMed Central

2015-01-01

Shape-controlled synthesis of nanomaterials through a simple, continuous, and low-cost method is essential to nanomaterials research toward practical applications. Hydrodynamic focusing, with its advantages of simplicity, low-cost, and precise control over reaction conditions, has been used for nanomaterial synthesis. While most studies have focused on improving the uniformity and size control, few have addressed the potential of tuning the shape of the synthesized nanomaterials. Here we demonstrate a facile method to synthesize hybrid materials by three-dimensional hydrodynamic focusing (3D-HF). While keeping the flow rates of the reagents constant and changing only the flow rate of the buffer solution, the molar ratio of two reactants (i.e., tetrathiafulvalene (TTF) and HAuCl4) within the reaction zone varies. The synthesized TTF–Au hybrid materials possess very different and predictable morphologies. The reaction conditions at different buffer flow rates are studied through computational simulation, and the formation mechanisms of different structures are discussed. This simple one-step method to achieve continuous shape-tunable synthesis highlights the potential of 3D-HF in nanomaterials research. PMID:25268035

Shape-controlled synthesis of hybrid nanomaterials via three-dimensional hydrodynamic focusing.

PubMed

Lu, Mengqian; Yang, Shikuan; Ho, Yi-Ping; Grigsby, Christopher L; Leong, Kam W; Huang, Tony Jun

2014-10-28

Shape-controlled synthesis of nanomaterials through a simple, continuous, and low-cost method is essential to nanomaterials research toward practical applications. Hydrodynamic focusing, with its advantages of simplicity, low-cost, and precise control over reaction conditions, has been used for nanomaterial synthesis. While most studies have focused on improving the uniformity and size control, few have addressed the potential of tuning the shape of the synthesized nanomaterials. Here we demonstrate a facile method to synthesize hybrid materials by three-dimensional hydrodynamic focusing (3D-HF). While keeping the flow rates of the reagents constant and changing only the flow rate of the buffer solution, the molar ratio of two reactants (i.e., tetrathiafulvalene (TTF) and HAuCl4) within the reaction zone varies. The synthesized TTF-Au hybrid materials possess very different and predictable morphologies. The reaction conditions at different buffer flow rates are studied through computational simulation, and the formation mechanisms of different structures are discussed. This simple one-step method to achieve continuous shape-tunable synthesis highlights the potential of 3D-HF in nanomaterials research.

Continuous subcutaneous insulin infusion: Special needs for children.

PubMed

Adolfsson, Peter; Ziegler, Ralph; Hanas, Ragnar

2017-06-01

Continuous subcutaneous insulin infusion (CSII) is a very common therapy for children with type 1 diabetes. Due to physiological differences they have other requirements for their insulin pump than adults. The main difference is the need for very low basal rates. Even though most available insulin pumps reach a high accuracy at usual basal rates, accuracy decreases for lower rates. In addition, the lowest delivered amount at 1 time is limiting the fine tuning of the basal rate as well as the option for temporary basal rates. Alarms in case of occlusions depend on accumulation of a certain amount of insulin in the catheter, and therefore the time until such an alarm is triggered is much longer with lower basal rates. Accordingly, the risk for hyperglycemia developing into diabetic ketoacidosis increases. The availability of bolus advisors facilitates the calculation of meal and correction boluses for children and their parents. However, there are some differences between the calculators, and the settings that the calculation is based on are very important. Better connectivity, for example with a system for continuous glucose monitoring, might help to further increase safety in the use of CSII in children. When selecting an insulin pump for a child, the features and characteristics of available pumps should be properly compared to ensure an effective and safe therapy. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Predictive factors in patients with hepatocellular carcinoma receiving sorafenib therapy using time-dependent receiver operating characteristic analysis.

PubMed

Nishikawa, Hiroki; Nishijima, Norihiro; Enomoto, Hirayuki; Sakamoto, Azusa; Nasu, Akihiro; Komekado, Hideyuki; Nishimura, Takashi; Kita, Ryuichi; Kimura, Toru; Iijima, Hiroko; Nishiguchi, Shuhei; Osaki, Yukio

2017-01-01

To investigate variables before sorafenib therapy on the clinical outcomes in hepatocellular carcinoma (HCC) patients receiving sorafenib and to further assess and compare the predictive performance of continuous parameters using time-dependent receiver operating characteristics (ROC) analysis. A total of 225 HCC patients were analyzed. We retrospectively examined factors related to overall survival (OS) and progression free survival (PFS) using univariate and multivariate analyses. Subsequently, we performed time-dependent ROC analysis of continuous parameters which were significant in the multivariate analysis in terms of OS and PFS. Total sum of area under the ROC in all time points (defined as TAAT score) in each case was calculated. Our cohort included 175 male and 50 female patients (median age, 72 years) and included 158 Child-Pugh A and 67 Child-Pugh B patients. The median OS time was 0.68 years, while the median PFS time was 0.24 years. On multivariate analysis, gender, body mass index (BMI), Child-Pugh classification, extrahepatic metastases, tumor burden, aspartate aminotransferase (AST) and alpha-fetoprotein (AFP) were identified as significant predictors of OS and ECOG-performance status, Child-Pugh classification and extrahepatic metastases were identified as significant predictors of PFS. Among three continuous variables (i.e., BMI, AST and AFP), AFP had the highest TAAT score for the entire cohort. In subgroup analyses, AFP had the highest TAAT score except for Child-Pugh B and female among three continuous variables. In continuous variables, AFP could have higher predictive accuracy for survival in HCC patients undergoing sorafenib therapy.

Development of synchronized, autonomous, and self-regulated oscillations in transpiration rate of a whole tomato plant under water stress.

PubMed

Wallach, Rony; Da-Costa, Noam; Raviv, Michael; Moshelion, Menachem

2010-07-01

Plants respond to many environmental changes by rapidly adjusting their hydraulic conductivity and transpiration rate, thereby optimizing water-use efficiency and preventing damage due to low water potential. A multiple-load-cell apparatus, time-series analysis of the measured data, and residual low-pass filtering methods were used to monitor continuously and analyse transpiration of potted tomato plants (Solanum lycopersicum cv. Ailsa Craig) grown in a temperature-controlled greenhouse during well-irrigated and drought periods. A time derivative of the filtered residual time series yielded oscillatory behaviour of the whole plant's transpiration (WPT) rate. A subsequent cross-correlation analysis between the WPT oscillatory pattern and wet-wick evaporation rates (vertical cotton fabric, 0.14 m(2) partly submerged in water in a container placed on an adjacent load cell) revealed that autonomous oscillations in WPT rate develop under a continuous increase in water stress, whereas these oscillations correspond with the fluctuations in evaporation rate when water is fully available. The relative amplitude of these autonomous oscillations increased with water stress as transpiration rate decreased. These results support the recent finding that an increase in xylem tension triggers hydraulic signals that spread instantaneously via the plant vascular system and control leaf conductance. The regulatory role of synchronized oscillations in WPT rate in eliminating critical xylem tension points and preventing embolism is discussed.

Factors that impact clinical laboratory scientists' commitment to their work organizations.

PubMed

Bamberg, Richard; Akroyd, Duane; Moore, Ti'eshia M

2008-01-01

To assess the predictive ability of various aspects of the work environment for organizational commitment. A questionnaire measuring three dimensions of organizational commitment along with five aspects of work environment and 10 demographic and work setting characteristics was sent to a national, convenience sample of clinical laboratory professionals. All persons obtaining the CLS certification by NCA from January 1, 1997 to December 31, 2006. Only respondents who worked full-time in a clinical laboratory setting were included in the database. Levels of affective, normative, and continuance organizational commitment, organizational support, role clarity, role conflict, transformational leadership behavior of supervisor, and organizational type, total years work experience in clinical laboratories, and educational level of respondents. Questionnaire items used either a 7-point or 5-point Likert response scale. Based on multiple regression analysis for the 427 respondents, organizational support and transformational leadership behavior were found to be significant positive predictors of affective and normative organizational commitment. Work setting (non-hospital laboratory) and total years of work experience in clinical laboratories were found to be significant positive predictors of continuance organizational commitment. Overall the organizational commitment levels for all three dimensions were at the neutral rating or below in the slightly disagree range. The results indicate a less than optimal level of organizational commitment to employers, which were predominantly hospitals, by CLS practitioners. This may result in continuing retention problems for hospital laboratories. The results offer strategies for improving organizational commitment via the significant predictors.

Dynamics of the cascade capture of electrons by charged donors in GaAs and InP

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

Aleshkin, V. Ya., E-mail: aleshkin@ipmras.ru; Gavrilenko, L. V.

2016-08-15

The times for the cascade capture of an electron by a charged impurity have been calculated for pulsed and stationary excitations of impurity photoconductivity in GaAs and InP. The characteristic capture times under pulsed and continuous excitations are shown to differ noticeably both from each other and from the value given by the Abakumov–Perel–Yassievich formula for a charged impurity concentration greater than 10{sup 10} cm{sup –3}. The cause of this difference has been established. The Abakumov–Perel–Yassievich formula for the cascade capture cross section in the case of stationary excitation has been generalized. The dependences of the cascade capture rate onmore » the charged impurity concentration in GaAs and InP have been found for three temperatures in the case of pulsed excitation.« less

Audiologists' communication behaviour during hearing device management appointments.

PubMed

Muñoz, Karen; Ong, Clarissa W; Borrie, Stephanie A; Nelson, Lauri H; Twohig, Michael P

2017-05-01

The aim of this exploratory study was to describe audiologist communication behaviours during appointments for hearing device monitoring and management before and after participation in counselling skills training. The study used a longitudinal design with three assessment points over 6 months. The sample included 10 audiologists and audiology graduate students interacting in a professional setting with their clients. Audiologists reported improvement in their counselling skills from pre-training to follow-up, which was consistent with objective findings that audiologist relative speaking time decreased from pre-training to post-training as well as from pre-training to follow-up. Observer-rated scores of participants' counselling skills; however, yielded no significant differences across time. Some improvement was noted in audiologists' counselling behaviour following a 1-day communication skills workshop and continued learning support. It is evident; however, that further training, such as increased training and performance feedback, is needed to maintain and enhance audiologist progress in the various aspects of counselling.

EEG indices correlate with sustained attention performance in patients affected by diffuse axonal injury.

PubMed

Coelli, Stefania; Barbieri, Riccardo; Reni, Gianluigi; Zucca, Claudio; Bianchi, Anna Maria

2018-06-01

The aim of this study is to assess the ability of EEG-based indices in providing relevant information about cognitive engagement level during the execution of a clinical sustained attention (SA) test in healthy volunteers and DAI (diffused axonal injury)-affected patients. We computed three continuous power-based engagement indices (P β /P α , 1/P α , and P β / (P α + P θ )) from EEG recordings in a control group (n = 7) and seven DAI-affected patients executing a 10-min Conners' "not-X" continuous performance test (CPT). A correlation analysis was performed in order to investigate the existence of relations between the EEG metrics and behavioral parameters in both the populations. P β /P α and 1/P α indices were found to be correlated with reaction times in both groups while P β / (P α + P θ ) and P β /P α also correlated with the errors rate for DAI patients. In line with previous studies, time course fluctuations revealed a first strong decrease of attention after 2 min from the beginning of the test and a final fading at the end. Our results provide evidence that EEG-derived indices extraction and evaluation during SA tasks are helpful in the assessment of attention level in healthy subjects and DAI patients, offering motivations for including EEG monitoring in cognitive rehabilitation practice. Graphical abstract Three EEG-derived indices were computed from four electrodes montages in a population of seven healthy volunteers and a group of seven DAI-affected patients. Results show a significant correlation between the time course of the indices and behavioral parameters, thus demonstrating their usefulness in monitoring mental engagement level during a sustained attention task.

Discrete-state representation of ion permeation coupled to fast gating in a model of ClC chloride channels: comparison to multi-ion continuous space Brownian dynamics simulations.

PubMed

Coalson, Rob D; Cheng, Mary Hongying

2010-01-28

A discrete-state model of chloride ion motion in a ClC chloride channel is constructed, following a previously developed multi-ion continuous space model of the same system (Cheng, M. H.; Mamonov, A. B.; Dukes, J. W.; Coalson, R. D. J. Phys. Chem. B 2007, 111, 5956) that included a simplistic representation of the fast gate in this channel. The reducibility of the many-body continuous space to the eight discrete-state model considered in the present work is examined in detail by performing three-dimensional Brownian dynamics simulations of each allowed state-to-state transition in order to extract the appropriate rate constant for this process, and then inserting the pairwise rate constants thereby obtained into an appropriate set of kinetic master equations. Experimental properties of interest, including the rate of Cl(-) ion permeation through the open channel and the average rate of closing of the fast gate as a function of bulk Cl(-) ion concentrations in the intracellular and extracellular electrolyte reservoirs are computed. Good agreement is found between the results obtained via the eight discrete-state model versus the multi-ion continuous space model, thereby encouraging continued development of the discrete-state model to include more complex behaviors observed experimentally in these channels.

Phase transformations in steel studied by 3DXRD microscopy

NASA Astrophysics Data System (ADS)

Offerman, S. E.; van Dijk, N. H.; Sietsma, J.; Lauridsen, E. M.; Margulies, L.; Grigull, S.; Poulsen, H. F.; van der Zwaag, S.

2006-05-01

The ferrite grain nucleation mechanism during the austenite/ferrite phase transformation is studied in situ in the bulk of three different steel grades by three-dimensional X-ray diffraction (3DXRD) microscopy. The main difference between the three steel grades is the carbon concentration. For each steel grade the ferrite fraction, nucleus density and nucleation rate are measured simultaneously during continuous cooling. By comparing the measured nucleation rate to the classical nucleation theory it is concluded that the activation energy for ferrite nucleation is about two orders of magnitude smaller than the current models predict for the three steel grades. During slow cooling the same nucleation behaviour is found for the three steel grades concerning the balance between the energy that is released by the elimination of interfaces and the energy that is required for the formation new interfaces during ferrite nucleation.

Markov reward processes

NASA Technical Reports Server (NTRS)

Smith, R. M.

1991-01-01

Numerous applications in the area of computer system analysis can be effectively studied with Markov reward models. These models describe the behavior of the system with a continuous-time Markov chain, where a reward rate is associated with each state. In a reliability/availability model, upstates may have reward rate 1 and down states may have reward rate zero associated with them. In a queueing model, the number of jobs of certain type in a given state may be the reward rate attached to that state. In a combined model of performance and reliability, the reward rate of a state may be the computational capacity, or a related performance measure. Expected steady-state reward rate and expected instantaneous reward rate are clearly useful measures of the Markov reward model. More generally, the distribution of accumulated reward or time-averaged reward over a finite time interval may be determined from the solution of the Markov reward model. This information is of great practical significance in situations where the workload can be well characterized (deterministically, or by continuous functions e.g., distributions). The design process in the development of a computer system is an expensive and long term endeavor. For aerospace applications the reliability of the computer system is essential, as is the ability to complete critical workloads in a well defined real time interval. Consequently, effective modeling of such systems must take into account both performance and reliability. This fact motivates our use of Markov reward models to aid in the development and evaluation of fault tolerant computer systems.

Analysis and classification of bedload transport events with variable process characteristics

NASA Astrophysics Data System (ADS)

Kreisler, Andrea; Moser, Markus; Aigner, Johann; Rindler, Rolf; Tritthart, Michael; Habersack, Helmut

2017-08-01

Knowledge about the magnitude of bedload fluxes at given hydraulic conditions in natural streams is essential for improved process understanding, for the application, calibration and validation of bedload transport formulas, and for numerical sediment transport models. Nonetheless, extensive field measurements of bedload transport are challenging and therefore data from such efforts are rare. Bedload transport has been measured comprehensively at the downstream section of the Urslau torrent in Salzburg, Austria, since 2011. We used an integrative monitoring system that combines direct (mobile basket sampler, slot sampler) and indirect measuring devices (geophone plates). Continuous information about the intensity and distribution of bedload transport within the channel cross-section is available in high spatial and temporal resolution. Seven geophone plates at a stream width of 8 m are part of a measurement system that delivers data in 1-min intervals. These geophone data are calibrated using results of direct bedload measurements, providing an opportunity to calculate bedload rates and bedload yields in selected time periods. Continuous data on the bedload transport process over three years enabled assessing several bedload transport events. The investigation of bedload transport rate/discharge relationships reveals order-of-magnitude changes. For individual events, we observed shifts in the data, reflecting different bedload rates at comparable hydraulic conditions. This study reveals that variable sediment supply conditions affect the prevailing bedload transport rates at the Urslau stream. Calculating the bedload transport efficiency enables comparing bedload transport events that exhibit similar process characteristics. Finally, we provide a conceptual model of bedload transport process types as a function of bedload transport efficiency and dimensionless stream power.

Remembering the dynamic changes in pain intensity and unpleasantness: a psychophysical study.

PubMed

Khoshnejad, Mina; Fortin, Marie C; Rohani, Farzan; Duncan, Gary H; Rainville, Pierre

2014-03-01

This study investigated the short-term memory of dynamic changes in acute pain using psychophysical methods. Pain intensity or unpleasantness induced by painful contact-heat stimuli of 8, 9, or 10s was rated continuously during the stimulus or after a 14-s delay using an electronic visual analog scale in 10 healthy volunteers. Because the continuous visual analog scale time courses contained large amounts of redundant information, a principal component analysis was applied to characterize the main features inherent to both the concurrent rating and retrospective evaluations. Three components explained about 90% of the total variance across all trials and subjects, with the first component reflecting the global perceptual profile, and the second and third components explaining finer perceptual aspects (eg, changes in slope at onset and offset and shifts in peak latency). We postulate that these 3 principal components may provide some information about the structure of the mental representations of what one perceives, stores, and remembers during the course of few seconds. Analysis performed on the components confirmed significant memory distortions and revealed that the discriminative information about pain dimensions in concurrent ratings was partly or completely lost in retrospective ratings. Importantly, our results highlight individual differences affecting these memory processes. These results provide further evidence of the important transformations underlying the processing of pain in explicit memory and raise fundamental questions about the conversion of dynamic nociceptive signals into a mental representation of pain in perception and memory. Copyright © 2013 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.

Postearthquake relaxation after the 2004 M6 Parkfield, California, earthquake and rate-and-state friction

USGS Publications Warehouse

Savage, J.C.; Langbein, J.

2008-01-01

An unusually complete set of measurements (including rapid rate GPS over the first 10 days) of postseismic deformation is available at 12 continuous GPS stations located close to the epicenter of the 2004 M6.0 Parkfield earthquake. The principal component modes for the relaxation of the ensemble of those 12 GPS stations were determined. The first mode alone furnishes an adequate approximation to the data. Thus, the relaxation at all stations can be represented by the product of a common temporal function and distinct amplitudes for each component (north or east) of relaxation at each station. The distribution in space of the amplitudes indicates that the relaxation is dominantly strike slip. The temporal function, which spans times from about 5 min to 900 days postearthquake, can be fit by a superposition of three creep terms, each of the form ??l loge(1 + t/??l), with characteristic times ??, = 4.06, 0.11, and 0.0001 days. It seems likely that what is actually involved is a broad spectrum of characteristic times, the individual components of which arise from afterslip on different fault patches. Perfettini and Avouac (2004) have shown that an individual creep term can be explained by the spring-slider model with rate-dependent (no state variable) friction. The observed temporal function can also be explained using a single spring-slider model (i.e., single fault patch) that includes rate-and-state-dependent friction, a single-state variable, and either of the two commonly used (aging and slip) state evolution laws. In the latter fits, the rate-and-state friction parameter b is negative.

Long-term patency of complex bilobular, bisaccular, and broad-neck aneurysms in the rabbit microsurgical venous pouch bifurcation model.

PubMed

Marbacher, Serge; Tastan, Ilhan; Neuschmelting, Volker; Erhardt, Salome; Coluccia, Daniel; Sherif, Camillo; Remonda, Luca; Fandino, Javier

2012-07-01

In experimental aneurysm models, long-term patency without spontaneous thrombosis is the most important precondition for analyses of embolization devices. We recently reported the feasibility of creating complex venous pouch bifurcation aneurysms in the rabbit with low morbidity, low mortality, and high short-term aneurysm patency. In order to further evaluate our model, we examined the long-term patency rate. Various sizes of complex bilobular, bisaccular, and broad-neck venous pouch aneurysms were surgically formed at an artificially created bifurcation of both common carotid arteries in 17 rabbits. Early aggressive anticoagulation was continued for 1 month. The rabbits were followed up using contrast-enhanced three-dimensional 1.5-T magnetic resonance angiography (CE-3D-MRA) at 1 month and up to 1 year after creation of the bifurcation. At 1-month follow-up, all but one of the created aneurysms and all parent vessels proved to be patent. Three animals (18%) were lost during follow-up for reasons unrelated to aneurysm surgery. At 1-year follow-up, one animal showed partial and one complete spontaneous aneurysm thrombosis (aneurysm patency rate: 86%). Six out of 42 parent vessels were occluded at that time (vessel patency rate: 86%). Complex bilobular, bisaccular, and broad-neck microsurgical aneurysm formation in the rabbit bifurcation model demonstrates a high long-term patency rate but is complicated by high rates of unrelated procedural mortality and morbidity. There is no need for prolonged (>4 weeks) anticoagulation to achieve good long-term patency in complex venous pouch bifurcation aneurysms.

National survey on turnaround time of clinical biochemistry tests in 738 laboratories in China.

PubMed

Zhang, Xiaoyan; Fei, Yang; Wang, Wei; Zhao, Haijian; Wang, Minqi; Chen, Bingquan; Zhou, Jie; Wang, Zhiguo

2018-02-01

This survey was initiated to estimate the current status of turnaround time (TAT) monitoring of clinical biochemistry in China, provide baseline data for establishment of quality specifications and analyze the impact factors of TAT. 738 laboratories were included. Questionnaires involved general information and data of related indicators of TAT during 1 week were provided to participating laboratories. Nine quality indicators were covered, which were medians, 90th and outlier rates of pre-examination, examination, and post-examination TAT. The 25th percentile, median, and 75th percentile of TATs were calculated as optimum, desirable, and minimum quality specifications. Percentages and sigma values were used to describe the outlier rates. Mann-Whitney and Kruskal-Wallis tests were used to identify the potential impacts of TAT. Response rate of this survey was 46.44%. More than 50% of the laboratories indicated they had set up target TATs in three time intervals and monitored TATs generally. The post-examination TAT of most laboratories was 0min, while the pre-examination and examination TAT varied. Sigma values of outlier rates for 45%~60% of laboratories were above 4, while 15%~20% of labs whose sigma values were below 3. Group comparisons suggested nurse or mechanical pipeline transportation, link laboratory information system with hospital information system, and using computer reporting instead of printing report were related to shorter TATs. Despite of the remarkable progresses of TATs in China, there was also room to improve. Laboratories should strengthen the construction of information systems, identify reasons for TAT delay to improve the service quality continuously. © 2017 Wiley Periodicals, Inc.

Potential epidemiologic, economic, and budgetary impacts of current rates of hepatitis C treatment in medicare and non-medicare populations.

PubMed

Wittenborn, John; Brady, Joanne; Dougherty, Michelle; Rein, David

2017-04-01

We forecast the health and budgetary impact of hepatitis C (HCV) treatment on the Medicare program based on currently observed rates of treatment among Medicare and non-Medicare patients and identify the impact of higher rates of treatment among non-Medicare populations. We developed a computer microsimulation model to conduct an epidemiologic forecast, a budgetary impact analysis, and a cost-effectiveness analysis of the treatment of HCV based on three scenarios: 1) no treatment, 2) continuation of current-treatment rates, and 3) treatment rates among non-Medicare patients increased to match that of Medicare patients. The simulated population is based on National Health and Nutrition Examination Survey data. HCV progression rates and costs were calculated in Surveillance, Epidemiology, and End Results Program Medicare 5% claims data from the Chronic Hepatitis Cohort Study and published literature. We estimate that 13.6% of patients with HCV in the United States are enrolled in Medicare, but 75% will enter Medicare in the next 20 years. Medicare patients were over 5 times as likely to be treated in 2014-2015 as other patients. Medicare paid over $9 billion in treatment costs in both 2015 and 2016 and will total $28.4 billion from 2017-2026. Increasing treatment rates among non-Medicare patients would lead to 234,000 more patients being treated, reduce HCV mortality by 19%, and decrease Medicare costs by $18.6 billion from 2017-2026. We find that treatment remains cost-effective under most assumptions, costing $31,718 per quality adjusted life year gained. Conclusion : Medicare treats a disproportionately large share of HCV patients. Continued low rates of treatment among non-Medicare HCV patients will result in both reduced and deferred treatment, shifting future treatment costs to Medicare while increasing overall medical management costs, morbidity, and mortality. ( Hepatology Communications 2017;1:99-109).

Analysis of different fractionations of three-dimensional conformable radiotherapy for esophageal cancer.

PubMed

Ma, Zhiqian; Zhang, Yan; Chen, Xiaofang; Liu, Chaoxing; Xu, Huijun; Zhao, Peng

2015-01-01

This study aims to observe and discuss the curative and side effects of three different fractionation regimen of three-dimensional conformable radiotherapy (3DCRT) for esophageal cancer. A total of 169 untreated patients of esophageal cancer were randomized into three groups: groups A (conventional group, 2.0 Gy per time), B (2.5 Gy group, 2 Gy per time), and C (3.0 Gy group, 3.0 Gy per time), respectively. Groups A, B, and C are similar in terms of partial response (P = 0.35). However, the three groups had no significant differences in terms of the complete response (P = 0.63). The three-year survival rate of group B was higher than those of the other two groups, and the difference was significant (P = 0.047). For the three-year local control rate, that of group B was also higher than those of groups A and C, but the difference was not significant (P = 0.067). The incidence rate of 3 level esophagitis and bronchitis was highest in group C (P = 0.023 and P = 0.064). The 3 level tardive radioactive esophagitis in group C was higher than those in other two groups (P = 0.037 and P = 0.04). The incidence rate of the 3 level advanced lung reaction was also the highest in the three groups (P = 0.041). The effect is better and the side effect is tolerable for the 2.5 Gy per fraction, 5 times per week; thus, it can be used clinically for 3DCRT for esophageal carcinoma.

Sound envelope encoding in the auditory cortex revealed by neuromagnetic responses in the theta to gamma frequency bands.

PubMed

Miyazaki, Takahiro; Thompson, Jessica; Fujioka, Takako; Ross, Bernhard

2013-04-19

Amplitude fluctuations of natural sounds carry multiple types of information represented at different time scales, such as syllables and voice pitch in speech. However, it is not well understood how such amplitude fluctuations at different time scales are processed in the brain. In the present study we investigated the effect of the stimulus rate on the cortical evoked responses using magnetoencephalography (MEG). We used a two-tone complex sound, whose envelope fluctuated at the difference frequency and induced an acoustic beat sensation. When the beat rate was continuously swept between 3Hz and 60Hz, auditory evoked response showed distinct transient waves at slow rates, while at fast rates continuous sinusoidal oscillations similar to the auditory steady-state response (ASSR) were observed. We further derived temporal modulation transfer functions (TMTF) from amplitudes of the transient responses and from the ASSR. The results identified two critical rates of 12.5Hz and 25Hz, at which consecutive transient responses overlapped with each other. These stimulus rates roughly corresponded to the rates at which the perceptual quality of the sound envelope is known to change. Low rates (> 10Hz) are perceived as loudness fluctuation, medium rates as acoustical flutter, and rates above 25Hz as roughness. We conclude that these results reflect cortical processes that integrate successive acoustic events at different time scales for extracting complex features of natural sound. Copyright © 2013 Elsevier B.V. All rights reserved.

How Do Private Health Plans Manage Specialty Behavioral Health Treatment Entry and Continuing Care?

PubMed

Quinn, Amity E; Reif, Sharon; Merrick, Elizabeth L; Horgan, Constance M; Garnick, Deborah W; Stewart, Maureen T

2017-09-01

This study examined private health plans' arrangements for accessing and continuing specialty behavioral health treatment in 2010 as federal health reforms were being implemented. These management practices have historically been stricter in behavioral health care than in general medical care; however, the Mental Health Parity and Addiction Equity Act of 2010 required parity in management policies. The data source was a nationally representative survey of private health plans' behavioral health treatment management approaches in 2010. Health plan executives were asked about activities for their plan's three products with highest enrollment (weighted N=8,427, 88% response rate). Prior authorization for outpatient behavioral health care was rarely required (4.7% of products), but 75% of products required authorization for ongoing care and over 90% required prior authorization for other levels of care. The most common medical necessity criteria were self-developed and American Society of Addiction Medicine criteria. Nearly all products had formal standards to limit waiting time for routine and urgent treatment, but almost 30% lacked such standards for detoxification services. A range of wait time-monitoring approaches was used. Health plans used a variety of methods to influence behavioral health treatment entry and continuing care. Few relied on prior authorization for outpatient care, but the use of other approaches to influence, manage, or facilitate access was common. Results provide a baseline for understanding the current management environment for specialty behavioral health care. Tracking health plans' approaches over time will be important to ensure that access to behavioral health care is not prohibitively restrictive.

Intensification of antiretroviral treatment with raltegravir for pregnant women living with HIV at high risk of vertical transmission.

PubMed

Puthanakit, Thanyawee; Thepnarong, Nattawan; Chaithongwongwatthana, Surasith; Anugulruengkitt, Suvaporn; Anunsittichai, Orawan; Theerawit, Tuangtip; Ubolyam, Sasiwimol; Pancharoen, Chitsanu; Phanuphak, Praphan

2018-04-01

Objectives:  The rate of vertical HIV transmission for women at high risk of HIV transmission stands at approximately 7.6%. In the present study we describe infant infection rates in women who had received raltegravir (RAL) intensification during pregnancy to a standard three-drug antiretroviral (ART) regimen in Thailand. Methods:  This prospective cohort study enrolled HIV-1-positive pregnant women at high risk of vertical transmission, as defined by (1) ART initiation at a gestational age (GA) ≥32 weeks or (2) HIV-1 RNA >1000 copies/mL at GA of 32-38 weeks while on ART. Women received a standard three-drug ART regimen with RAL intensification (400 mg twice daily) until delivery and continued on a three-drug ART regimen after delivery. Plasma HIV-1 RNA testing was performed before intensification and at delivery. Infant HIV-1 status was determined using DNA PCR at birth, and at 1, 2 and 4 months of life. Results:  Between February 2016 and November 2017, 154 pregnant women on ART were enrolled into the study with a median CD4 cell count and plasma HIV-1 RNA level of 382 cells/mm 3 and 4.0 log 10 copies/mL, respectively. The three-drug combination consisted of either a lopinavir/ritonavir- (53%) or efavirenz-based (43%) regimen. Median GA at time of RAL initiation was 34 weeks (interquartile range [IQR] 33-36) and median duration was 21 days (IQR 8-34). The proportion of women who had a plasma HIV-1 RNA <50 and <1000 copies/mL at delivery was 45% and 76%, respectively. There were six infants with HIV infection, three in utero and three peripartum. Overall vertical transmission rate was 3.9% (95% confidence interval [CI] 1.4-8.2). Conclusion:  The majority of high-risk pregnant women living with HIV-1 who had received RAL intensification achieved viral suppression at delivery with a relatively low rate of vertical transmission. This intensification strategy represents an option for prevention in HIV-positive women at high risk of vertical transmission.

Improving primary care in British Columbia, Canada: evaluation of a peer-to-peer continuing education program for family physicians.

PubMed

MacCarthy, Dan; Kallstrom, Liza; Kadlec, Helena; Hollander, Marcus

2012-11-09

An innovative program, the Practice Support Program (PSP), for full-service family physicians and their medical office assistants in primary care practices was recently introduced in British Columbia, Canada. The PSP was jointly approved by both government and physician groups, and is a dynamic, interactive, educational and supportive program that offers peer-to-peer training to physicians and their office staff. Topic areas range from clinical tools/skills to office management relevant to General Practitioner (GP) practices and "doable in real GP time". PSP learning modules consist of three half-day learning sessions interspersed with 6-8 week action periods. At the end of the third learning session, all participants were asked to complete a pen-and-paper survey that asked them to rate (a) their satisfaction with the learning module components, including the content and (b) the perceived impact the learning has had on their practices and patients. A total of 887 GPs (response rates ranging from 26.0% to 60.2% across three years) and 405 MOAs (response rates from 21.3% to 49.8%) provided responses on a pen-and-paper survey administered at the last learning session of the learning module. The survey asked respondents to rate (a) their satisfaction with the learning module components, including the content and (b) the perceived impact the learning has had on their practices and patients. The psychometric properties (Chronbach's alphas) of the satisfaction and impact scales ranged from .82 to .94. Evaluation findings from the first three years of the PSP indicated consistently high satisfaction ratings and perceived impact on GP practices and patients, regardless of physician characteristics (gender, age group) or work-related variables (e.g., time worked in family practice). The Advanced Access Learning Module, which offers tools to improve office efficiencies, decreased wait times for urgent, regular and third next available appointments by an average of 1.2, 3.3, and by 3.4 days across all physicians. For the Chronic Disease Management module, over 87% of all GP respondents developed a CDM patient registry and reported being able to take better care of their patients. After attending the Adult Mental Health module: 94.1% of GPs agreed that they felt more comfortable helping patients who required mental health care; over 82% agreed that their skills and their confidence in diagnosing and treating mental health conditions had improved; and 41.0% agreed that their frequency of prescribing medications, if appropriate, had decreased. Additionally for the Adult Mental Health module, a 3-6 month follow-up survey of the GPs indicated that the implemented changes were sustained over time. GP and medical office assistant participant ratings show that the PSP learning modules were consistently successful in providing GPs and their staff with new learning that was relevant and could be implemented and used in "real-GP-time".

Role of physical countermaneuvers in the management of orthostatic hypotension: efficacy and biofeedback augmentation

NASA Technical Reports Server (NTRS)

Bouvette, C. M.; McPhee, B. R.; Opfer-Gehrking, T. L.; Low, P. A.

1996-01-01

OBJECTIVE: To evaluate the efficacy of various physical countermaneuvers in reducing orthostatic hypotension and its associated symptoms and to assess the efficacy of biofeedback training in enhancing the effectiveness of physical countermaneuvers. MATERIAL AND METHODS: In nine study subjects with neurogenic orthostatic hypotension, four training sessions on physical countermaneuvers were performed after tilt-up, three with visual feedback on the effect of physical countermaneuvers on blood pressure and other cardiovascular variables. Blood pressure change and orthostatic symptoms during tilt-up were determined, as were the changes in total peripheral resistance, stroke index, and heart rate. RESULTS: The five female and four male patients had a mean age of 53 years and a mean duration of symptoms of 4.2 years. On an orthostatic symptom scale of 0 to 10, these patients had a mean symptom score of 7.3. The increment in systolic blood pressure was better for some maneuvers (such as leg crossing and a combination) than others (such as neck flexion and abdominal contraction). Three patterns of responses to biofeedback were found. Simple maneuvers such as squatting did not improve with training; visual feedback was needed for maneuvers such as thigh contraction, and performance declined without biofeedback; the third pattern, seen in maneuvers such as leg crossing, showed continued improvement with training, even without biofeedback. A survey at 3 to 4 months after training revealed continued use of physical maneuvers (3.8 +/- 3.1 per day), increased standing time with each episode of presyncopal symptoms (8.3 +/- 5.8 minutes), and continued global symptomatic improvement. Total peripheral resistance, but not heart rate or stroke index, showed significant regression with blood pressure improvement. CONCLUSION: Physical countermaneuvers are efficacious in reducing orthostatic hypotension, can be augmented by use of biofeedback, and may significantly improve the functional outcome. The major mechanism of improvement is an increase in total peripheral resistance, presumably by reducing the vascular capacitance.

Stochastic resetting in backtrack recovery by RNA polymerases

NASA Astrophysics Data System (ADS)

Roldán, Édgar; Lisica, Ana; Sánchez-Taltavull, Daniel; Grill, Stephan W.

2016-06-01

Transcription is a key process in gene expression, in which RNA polymerases produce a complementary RNA copy from a DNA template. RNA polymerization is frequently interrupted by backtracking, a process in which polymerases perform a random walk along the DNA template. Recovery of polymerases from the transcriptionally inactive backtracked state is determined by a kinetic competition between one-dimensional diffusion and RNA cleavage. Here we describe backtrack recovery as a continuous-time random walk, where the time for a polymerase to recover from a backtrack of a given depth is described as a first-passage time of a random walker to reach an absorbing state. We represent RNA cleavage as a stochastic resetting process and derive exact expressions for the recovery time distributions and mean recovery times from a given initial backtrack depth for both continuous and discrete-lattice descriptions of the random walk. We show that recovery time statistics do not depend on the discreteness of the DNA lattice when the rate of one-dimensional diffusion is large compared to the rate of cleavage.

Flight Crew Sleep in Long-Haul Aircraft Bunk Facilities: Survey Results

NASA Technical Reports Server (NTRS)

Rosekind, Mark R.; Miller, Donna L.; Gregory, Kevin B.; Dinges, David F.; Shafto, Michael G. (Technical Monitor)

1995-01-01

Modem long-haul aircraft can fly up to 16 continuous hours and provide a 24-hour, global capability. Extra (augmented) flight crew are available on long flights to allow planned rest periods, on a rotating basis, away from the flight deck in onboard crew rest facilities (2 bunks). A NASA/FAA study is under-way to examine the quantity and quality of sleep obtained in long-haul aircraft bunks and the factors that promote or interfere with that sleep. The first phase of the study involved a retrospective survey, followed by a second phase field study to collect standard polysomnographic data during inflight bunk sleep periods. A summary of the Phase I survey results are reported here. A multi-part 54-question retrospective survey was completed by 1,404 flight crew (37% return rate) at three different major US air carriers flying B747-100, 200, 400, and MD- 11 long-haul aircraft. The questions examined demographics, quantity and quality of sleep at home and in onboard bunks, factors that promote or interfere with sleep, and effects on subsequent performance and alertness. Flight crew reported a mean bunk sleep latency of 39.4 mins (SD=28.3 mins) (n=1,276) and a mean total sleep time of 2.2 hrs (SD=1.3 hrs) (n=603). (Different flight lengths could affect overall time available for sleep.) Crew rated 25 factors for their interference or promotion of bunk sleep. Figure I portrays the average ratings for each factor across all three carriers. A principal components analysis of the 25 factors revealed three areas that promoted bunk sleep: physiological (e.g., readiness for sleep), physical environment (e.g., bunk size, privacy), and personal comfort (e.g., blankets, pillows). Five areas were identified that interfered with sleep: environmental disturbance (e.g., background noise, turbulence), luminosity (e.g., lighting), personal disturbances (e.g., bathroom trips, random thoughts), environmental discomfort (e.g., low humidity, cold), and interpersonal disturbances (e.g., bunk partner).

Thermal sensitivity of mitochondrial respiration efficiency and protein phosphorylation in the clam Mercenaria mercenaria.

PubMed

Ulrich, P N; Marsh, A G

2009-01-01

The mitochondria of intertidal invertebrates continue to function when organisms are exposed to rapid substantial shifts in temperature. To test if mitochondrial physiology of the clam Mercenaria mercenaria is compromised under elevated temperatures, we measured mitochondrial respiration efficiency at 15 degrees C, 18 degrees C, and 21 degrees C using a novel, high-throughput, microplate respirometry methodology developed for this study. Though phosphorylating (state 3) and resting (state 4) respiration rates were unaffected over this temperature range, respiratory control ratios (RCRs: ratio of state 3 to state 4 respiration rates) decreased significantly above 18 degrees C (p < 0.05). The drop in RCR was not associated with reduction of phosphorylation efficiency, suggesting that, while aerobic scope of mitochondrial respiration is limited at elevated temperatures, mitochondria continue to efficiently produce adenosine triphosphate. We further investigated the response of clam mitochondria to elevated temperatures by monitoring phosphorylation of mitochondrial protein. Three proteins clearly demonstrated significant time- and temperature-specific phosphorylation patterns. The protein-specific patterns of phosphorylation may suggest that a suite of protein kinases and phosphatases regulate mitochondrial physiology in response to temperature. Thus, while aerobic scope of clam mitochondrial respiration is reduced at moderate temperatures, specific protein phosphorylation responses reflect large shifts in function that are initiated within the organelle at higher temperatures.

Impact of continuous positive airway pressure (CPAP) on the respiratory capacity of chronic kidney disease patients under hemodialysis treatment.

PubMed

Xavier, Vivian Bertoni; Roxo, Renata Spósito; Miorin, Luiz Antônio; Dos Santos Alves, Vera Lúcia; Dos Santos Sens, Yvoty Alves

2015-06-01

Chronic kidney disease (CKD) patients on long-term dialysis present changes in pulmonary function and respiratory muscle strength, negatively influencing physical capacity. To analyze the impact of a continuous positive airway pressure (CPAP) protocol on the respiratory capacity of CKD patients under hemodialysis. A randomized clinical trial was conducted involving 40 CKD patients 19-83 years old divided into two groups: control (n = 20) and CPAP (n = 20). Subjects were assessed on the respiratory muscle function test, maximal respiratory pressures, peak flow and 6-min walk test, at baseline and again at the 2-month follow-up. CPAP group patients were submitted to CPAP protocol (PEEP: 5 cm H2O, flow: 15 L/min, FiO2: 33 %) three times per week during hemodialysis sessions. The CPAP group showed higher forced vital capacity, forced expiratory volume in one second, peak expiratory flow, maximal inspiratory pressure, peak flow, as well as lower systolic blood pressure, heart rate, respiratory rate and Borg scale, in addition to a longer distance travelled on the 6-min walk test, compared with the control group. The introduction of a CPAP protocol during hemodialysis sessions had a positive impact on pulmonary function and physical capacity in CKD patients.

Shear rate analysis of water dynamic in the continuous stirred tank

NASA Astrophysics Data System (ADS)

Tulus; Mardiningsih; Sawaluddin; Sitompul, O. S.; Ihsan, A. K. A. M.

2018-02-01

Analysis of mixture in a continuous stirred tank reactor (CSTR) is an important part in some process of biogas production. This paper is a preliminary study of fluid dynamic phenomenon in a continuous stirred tank numerically. The tank is designed in the form of cylindrical tank equipped with a stirrer. In this study, it is considered that the tank is filled with water. Stirring is done with a stirring speed of 10rpm, 15rpm, 20rpm, and 25rpm. Mathematical modeling of stirred tank is derived. The model is calculated by using the finite element method that are calculated using CFD software. The result shows that the shear rate is high on the front end portion of the stirrer. The maximum shear rate tend to a stable behaviour after the stirring time of 2 second. The relation between the speed and the maximum shear rate is in the form of linear equation.

In situ investigation of high humidity stress corrosion cracking of 7075 aluminum alloy by three-dimensional (3D) X-ray synchrotron tomography

DOE PAGES

Singh, S. S.; Williams, J. J.; Lin, M. F.; ...

2014-05-14

In situ X-ray synchrotron tomography was used to investigate the stress corrosion cracking behavior of under-aged Al–Zn–Mg–Cu alloy in moisture. The discontinuous surface cracks (crack jumps) mentioned in the literature are actually a single continuous and tortuous crack when observed in three dimension (3D). Contrary to 2D measurements made at the surface which suggest non-uniform crack growth rates, 3D measurements of the crack length led to a much more accurate measurement of crack growth rates.

21 CFR 137.200 - Whole wheat flour.

Code of Federal Regulations, 2012 CFR

2012-04-01

... upward stroke, at the rate of about 150 times per minute. Turn the sieves about one-sixth of a revolution each time in the same direction, after each 25 strokes. Continue shaking for 2 minutes. Weigh the...

21 CFR 137.200 - Whole wheat flour.

Code of Federal Regulations, 2013 CFR

2013-04-01

... upward stroke, at the rate of about 150 times per minute. Turn the sieves about one-sixth of a revolution each time in the same direction, after each 25 strokes. Continue shaking for 2 minutes. Weigh the...

21 CFR 137.200 - Whole wheat flour.

Code of Federal Regulations, 2014 CFR

2014-04-01

... upward stroke, at the rate of about 150 times per minute. Turn the sieves about one-sixth of a revolution each time in the same direction, after each 25 strokes. Continue shaking for 2 minutes. Weigh the...

Effects of episodic sediment supply on bedload transport rate in mountain rivers. Detecting debris flow activity using continuous monitoring

NASA Astrophysics Data System (ADS)

Uchida, Taro; Sakurai, Wataru; Iuchi, Takuma; Izumiyama, Hiroaki; Borgatti, Lisa; Marcato, Gianluca; Pasuto, Alessandro

2018-04-01

Monitoring of sediment transport from hillslopes to channel networks as a consequence of floods with suspended and bedload transport, hyperconcentrated flows, debris and mud flows is essential not only for scientific issues, but also for prevention and mitigation of natural disasters, i.e. for hazard assessment, land use planning and design of torrent control interventions. In steep, potentially unstable terrains, ground-based continuous monitoring of hillslope and hydrological processes is still highly localized and expensive, especially in terms of manpower. In recent years, new seismic and acoustic methods have been developed for continuous bedload monitoring in mountain rivers. Since downstream bedload transport rate is controlled by upstream sediment supply from tributary channels and bed-external sources, continuous bedload monitoring might be an effective tool for detecting the sediments mobilized by debris flow processes in the upper catchment and thus represent an indirect method to monitor slope instability processes at the catchment scale. However, there is poor information about the effects of episodic sediment supply from upstream bed-external sources on downstream bedload transport rate at a single flood time scale. We have examined the effects of sediment supply due to upstream debris flow events on downstream bedload transport rate along the Yotagiri River, central Japan. To do this, we have conducted continuous bedload observations using a hydrophone (Japanese pipe microphone) located 6.4 km downstream the lower end of a tributary affected by debris flows. Two debris flows occurred during the two-years-long observation period. As expected, bedload transport rate for a given flow depth showed to be larger after storms triggering debris flows. That is, although the magnitude of sediment supply from debris flows is not large, their effect on bedload is propagating >6 km downstream at a single flood time scale. This indicates that continuous bedload observations could be effective for detecting sediment supply as a consequence of debris flow events.

Continuation and maintenance treatments for depression in older people.

PubMed

Wilkinson, Philip; Izmeth, Zehanah

2016-09-09

Depressive illness is common in old age. Prevalence in the community of case level depression is around 15% and milder forms of depression are more common. It causes significant distress and disability. The number of people over the age of 60 years is expected to double by 2050 and so interventions for this often long-term and recurrent condition are increasingly important. The causes of late-life depression differ from depression in younger adults and so it is appropriate to study it separately.This is an update of a Cochrane review first published in 2012. To examine the efficacy of antidepressants and psychological therapies in preventing the relapse and recurrence of depression in older people. We performed a search of the Cochrane Common Mental Disorders Group's specialised register (the CCMDCTR) to 13 July 2015. The CCMDCTR includes relevant randomised controlled trials (RCTs) from the following bibliographic databases: The Cochrane Library (all years), MEDLINE (1950 to date), EMBASE (1974 to date), and PsycINFO (1967 to date). We also conducted a cited reference search on 13 July 2015 of the Web of Science for citations of primary reports of included studies. Both review authors independently selected studies. We included RCTs involving people aged 60 years and over successfully treated for an episode of depression and randomised to receive continuation and maintenance treatment with antidepressants, psychological therapies, or a combination. Two review authors independently extracted data. The primary outcome for benefit was recurrence rate of depression (reaching a cut-off on any depression rating scale) at 12 months and the primary outcome for harm was drop-outs at 12 months. Secondary outcomes included relapse/recurrence rates at other time points, global impression of change, social functioning, and deaths. We performed meta-analysis using risk ratio (RR) for dichotomous outcomes and mean difference (MD) for continuous outcomes, with 95% confidence intervals (CI). This update identified no further trials. Seven studies from the previous review met the inclusion criteria (803 participants). Six compared antidepressant medication with placebo; two involved psychological therapies. There was marked heterogeneity between the studies.Comparing antidepressants with placebo on the primary outcome for benefit, there was a statistically significant difference favouring antidepressants in reducing recurrence compared with placebo at 12 months with a GRADE rating of low for quality of evidence (three RCTs, n = 247, RR 0.67, 95% CI 0.54 to 0.82; number needed to treat for an additional beneficial outcome (NNTB) 5). Comparing antidepressants with placebo on the primary outcome for harms, there was no difference in drop-out rates at 12 months' follow-up, with a GRADE rating of low.There was no significant difference between psychological treatment and antidepressant in recurrence rates at 12 months (one RCT, n = 53) or between combination treatment and antidepressant alone at 12 months. This updated Cochrane review supports the findings of the original 2012 review. The long-term benefits and harm of continuing antidepressant medication in the prevention of recurrence of depression in older people are not clear and no firm treatment recommendations can be made on the basis of this review. Continuing antidepressant medication for 12 months appears to be helpful with no increased harms; however, this was based on only three small studies, relatively few participants, use of a range of antidepressant classes, and clinically heterogeneous populations. Comparisons at other time points did not reach statistical significance.Data on psychological therapies and combined treatments were too limited to draw any conclusions on benefits and harms.The quality of the evidence used in reaching these conclusions was low and the review does not, therefore, offer clear guidance to clinicians and patients on best practice and matching interventions to particular patient characteristics.Of note, we identified no new studies that evaluated pharmacological or psychological interventions in the continuation and maintenance treatment of depression in older people. We are aware of studies conducted since the previous review that included both older people and adults under the age of 65 years, but these fall outside of the remit of this review. We believe that there remains a need for studies solely recruiting older people, particularly the 'older old' with comorbid medical problems. However, these studies are likely to be challenging to conduct and may not, so far, have been prioritised by funders.

Asymmetric B-factory note

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

Calderon, M.

Three main issues giving purpose to our visit to CERN, ESRF and DESY were to: assess the current thinking at CERN on whether Eta, the gas desorption coefficient, would continue to decrease with continued with continued beam cleaning, determine if the time between NEG reconditioning could be expanded, and acquire a knowledge of the basic fabrication processes and techniques for producing beam vacuum chambers of copper.

Time stretch and its applications

NASA Astrophysics Data System (ADS)

Mahjoubfar, Ata; Churkin, Dmitry V.; Barland, Stéphane; Broderick, Neil; Turitsyn, Sergei K.; Jalali, Bahram

2017-06-01

Observing non-repetitive and statistically rare signals that occur on short timescales requires fast real-time measurements that exceed the speed, precision and record length of conventional digitizers. Photonic time stretch is a data acquisition method that overcomes the speed limitations of electronic digitizers and enables continuous ultrafast single-shot spectroscopy, imaging, reflectometry, terahertz and other measurements at refresh rates reaching billions of frames per second with non-stop recording spanning trillions of consecutive frames. The technology has opened a new frontier in measurement science unveiling transient phenomena in nonlinear dynamics such as optical rogue waves and soliton molecules, and in relativistic electron bunching. It has also created a new class of instruments that have been integrated with artificial intelligence for sensing and biomedical diagnostics. We review the fundamental principles and applications of this emerging field for continuous phase and amplitude characterization at extremely high repetition rates via time-stretch spectral interferometry.

Kinetics of austenite-pearlite transformation in eutectoid carbon steel

NASA Astrophysics Data System (ADS)

Hawbolt, E. B.; Chau, B.; Brimacombe, J. K.

1983-09-01

The kinetics of the austenite-to-pearlite transformation have been measured under isothermal and continuous-cooling conditions on a eutectoid carbon (1080) steel using a diametral dilatometric technique. The isothermal transformation kinetics have been analyzed in terms of the Avrami Equation containing the two parameters n and b; the initiation of transformation was characterized by an empirically determined transformation-start time (tAv). The parameter n was found to be nearly constant; and neither n nor b was dependent on the cooling rate between T A1 and the test temperature. Continuous-cooling tests were performed with cooling rates ranging from 7.5 to 108 °C per second, and the initiation of transformation was determined. Comparison of this transformation-start time for different cooling rates with the measured slow cooling of a test coupon immersed in a salt bath indicates that, particularly at lower temperatures, the transformation in the traditional T-T-T test specimen may not be isothermal. The additivity rule was found to predict accurately the time taken, relative to tAv, to reach a given fraction of austenite transformed, even though there is some question that the isokinetic condition was met above 660 °C. However, the additivity rule does not hold for the pretransformation or incubation period, as originally proposed by Scheil, and seriously overestimates the incubation time. Application of the additivity rule to the prediction of transformation-finish time, based on transformation start at TA1, also leads to overestimates, but these are less serious. The isothermal parameters— n ( T), b ( T), and tAv ( T)—have been used to predict continuous-cooling transformation kinetics which are in close agreement with measurements at four cooling rates ranging from 7.5 to 64 °C per second.

The Barium Hydroxide-Ammonium Thiocyanate Reaction: A Titrimetric Continuous Variations Experiment.

ERIC Educational Resources Information Center

Harris, Arlo D.

1979-01-01

Presents an experiment for inorganic, organic, or physical chemistry students utilizing acid-base titrimetry to study the stoichiometric of a solid state reaction. Time involved ranges from one to three, three-hour lab periods. (Author/SA)

Neoadjuvant 5-FU or Capecitabine Plus Radiation With or Without Oxaliplatin in Rectal Cancer Patients: A Phase III Randomized Clinical Trial.

PubMed

Allegra, Carmen J; Yothers, Greg; O'Connell, Michael J; Beart, Robert W; Wozniak, Timothy F; Pitot, Henry C; Shields, Anthony F; Landry, Jerome C; Ryan, David P; Arora, Amit; Evans, Lisa S; Bahary, Nathan; Soori, Gamini; Eakle, Janice F; Robertson, John M; Moore, Dennis F; Mullane, Michael R; Marchello, Benjamin T; Ward, Patrick J; Sharif, Saima; Roh, Mark S; Wolmark, Norman

2015-11-01

National Surgical Adjuvant Breast and Bowel Project R-04 was designed to determine whether the oral fluoropyrimidine capecitabine could be substituted for continuous infusion 5-FU in the curative setting of stage II/III rectal cancer during neoadjuvant radiation therapy and whether the addition of oxaliplatin could further enhance the activity of fluoropyrimidine-sensitized radiation. Patients with clinical stage II or III rectal cancer undergoing preoperative radiation were randomly assigned to one of four chemotherapy regimens in a 2x2 design: CVI 5-FU or oral capecitabine with or without oxaliplatin. The primary endpoint was local-regional tumor control. Time-to-event endpoint distributions were estimated using the Kaplan-Meier method. Hazard ratios were estimated from Cox proportional hazard models. All statistical tests were two-sided. Among 1608 randomized patients there were no statistically significant differences between regimens using 5-FU vs capecitabine in three-year local-regional tumor event rates (11.2% vs 11.8%), 5-year DFS (66.4% vs 67.7%), or 5-year OS (79.9% vs 80.8%); or for oxaliplatin vs no oxaliplatin for the three endpoints of local-regional events, DFS, and OS (11.2% vs 12.1%, 69.2% vs 64.2%, and 81.3% vs 79.0%). The addition of oxaliplatin was associated with statistically significantly more overall and grade 3-4 diarrhea (P < .0001). Three-year rates of local-regional recurrence among patients who underwent R0 resection ranged from 3.1 to 5.1% depending on the study arm. Continuous infusion 5-FU produced outcomes for local-regional control, DFS, and OS similar to those obtained with oral capecitabine combined with radiation. This study establishes capecitabine as a standard of care in the pre-operative rectal setting. Oxaliplatin did not improve the local-regional failure rate, DFS, or OS for any patient risk group but did add considerable toxicity. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

A Regional Atmospheric Continuous CO2 Network In The Rocky Mountains (Rocky RACCOON)

NASA Astrophysics Data System (ADS)

Stephens, B.; de Wekker, S.; Watt, A.; Schimel, D.

2005-12-01

We have established a continuous CO2 observing network in the Rocky Mountains, building on technological and modeling advances made during the Carbon in the Mountains Experiment (CME), to improve our understanding of regional carbon fluxes and to fill key gaps in the North American Carbon Program (NACP). We will present a description of the Rocky RACCOON network and early results from the first three sites. There are strong scientific and societal motivations for determining CO2 exchanges on regional scales. NACP aims to address these concerns through a dramatic expansion in observations and modeling capabilities over North America. Mountain forests in particular represent a significant potential net CO2 sink in the U.S. and are highly sensitive to land-use practices and climate change. However, plans for new continuous CO2 observing sites have omitted the mountain west. This resulted from expensive instrumentation in the face of limited resources, and a perception that current atmospheric transport models are not sophisticated enough to interpret CO2 measurements made in complex terrain. Through our efforts in CME, we have a new autonomous, inexpensive, and robust CO2 analysis system and are developing mountain CO2 modeling tools that will help us to overcome these obstacles. Preliminary observational and modeling results give us confidence that continuous CO2 observations from mountain top observatories will provide useful constraints on regional carbon cycling and will be valuable in the continental inverse modeling efforts planned for NACP. We began at three Colorado sites in August 2005 and hope to add three to six sites in other western states in subsequent years, utilizing existing observatories to the maximum extent possible. The first three sites are at Niwot Ridge, allowing us to have an ongoing intercomparison with flask measurements made by NOAA CMDL; at Storm Peak Laboratory near Steamboat Springs, allowing us to investigate comparisons between these two relatively nearby sites; and at Fraser Experimental Forest, allowing us to investigate nocturnal respiration rates across a large intermountain valley. Our data are available to the public on the internet in near real time to support quality control, local science, and larger scale synthesis efforts.

Effective multiple stages continuous acetone-butanol-ethanol fermentation by immobilized bioreactors: Making full use of fresh corn stalk.

PubMed

Chang, Zhen; Cai, Di; Wang, Yong; Chen, Changjing; Fu, Chaohui; Wang, Guoqing; Qin, Peiyong; Wang, Zheng; Tan, Tianwei

2016-04-01

In order to make full use of the fresh corn stalk, the sugar containing juice was used as the sole substrate for acetone-butanol-ethanol production without any nutrients supplement, and the bagasse after squeezing the juice was used as the immobilized carrier. A total 21.34g/L of ABE was produced in batch cells immobilization system with ABE yield of 0.35g/g. A continuous fermentation containing three stages with immobilized cells was conducted and the effect of dilution rate on fermentation was investigated. As a result, the productivity and ABE solvents concentration reached 0.80g/Lh and 19.93g/L, respectively, when the dilution rate in each stage was 0.12/h (corresponding to a dilution rate of 0.04/h in the whole system). And the long-term operation indicated the continuous multiple stages ABE fermentation process had good stability and showed the great potential in future industrial applications. Copyright © 2016 Elsevier Ltd. All rights reserved.

Are local laws the key to ending childhood lead poisoning?

PubMed

Korfmacher, Katrina S; Hanley, Michael L

2013-08-01

Although lead paint was banned by federal law in 1978, it continues to poison children living in homes built before that time. The lifelong effects of childhood exposure to even small amounts of lead are well established by medical research. Federal and state laws have reduced rates of lead poisoning significantly in the past three decades. However, pockets of high rates of lead poisoning remain, primarily in low-income urban neighborhoods with older housing stock. Recently, several municipalities have passed local lead laws to reduce lead hazards in high-risk areas. There has been no systematic attempt to compare the design and effectiveness of these local policies. To address this gap, we conducted comparative case studies of eight innovative lead laws promulgated since 2000. The laws used a wide variety of legal structures and tools, although certain elements were common. The impact of the policies was intertwined with local housing, economic, and legal environments. While data do not yet exist to systematically evaluate the impact of these laws on lead poisoning rates, our analysis suggests that local laws hold great promise for reducing lead hazards in children's homes.

The effects of interval- vs. continuous exercise on excess post-exercise oxygen consumption and substrate oxidation rates in subjects with type 2 diabetes.

PubMed

Karstoft, Kristian; Wallis, Gareth A; Pedersen, Bente K; Solomon, Thomas P J

2016-09-01

For unknown reasons, interval training often reduces body weight more than energy-expenditure matched continuous training. We compared the acute effects of time-duration and oxygen-consumption matched interval- vs. continuous exercise on excess post-exercise oxygen consumption (EPOC), substrate oxidation rates and lipid metabolism in the hours following exercise in subjects with type 2 diabetes (T2D). Following an overnight fast, ten T2D subjects (M/F: 7/3; age=60.3±2.3years; body mass index (BMI)=28.3±1.1kg/m(2)) completed three 60-min interventions in a counterbalanced, randomized order: 1) control (CON), 2) continuous walking (CW), 3) interval-walking (IW - repeated cycles of 3min of fast and 3min of slow walking). Indirect calorimetry was applied during each intervention and repeatedly for 30min per hour during the following 5h. A liquid mixed meal tolerance test (MMTT, 450kcal) was consumed by the subjects 45min after completion of the intervention with blood samples taken regularly. Exercise interventions were successfully matched for total oxygen consumption (CW=1641±133mL/min; IW=1634±126mL/min, P>0.05). EPOC was higher after IW (8.4±1.3l) compared to CW (3.7±1.4l, P<0.05). Lipid oxidation rates were increased during the MMTT in IW (1.03±0.12mg/kg per min) and CW (0.87±0.04mg/kg per min) compared with CON (0.73±0.04mg/kg per min, P<0.01 and P<0.05, respectively), with no difference between IW and CW. Moreover, free fatty acids and glycerol concentrations, and glycerol kinetics were increased comparably during and after IW and CW compared to CON. Interval exercise results in greater EPOC than oxygen-consumption matched continuous exercise during a post-exercise MMTT in subjects with T2D, whereas effects on substrate oxidation and lipid metabolism are comparable. Copyright © 2016 Elsevier Inc. All rights reserved.

Dinosaurs in decline tens of millions of years before their final extinction

PubMed Central

Sakamoto, Manabu; Benton, Michael J.; Venditti, Chris

2016-01-01

Whether dinosaurs were in a long-term decline or whether they were reigning strong right up to their final disappearance at the Cretaceous–Paleogene (K-Pg) mass extinction event 66 Mya has been debated for decades with no clear resolution. The dispute has continued unresolved because of a lack of statistical rigor and appropriate evolutionary framework. Here, for the first time to our knowledge, we apply a Bayesian phylogenetic approach to model the evolutionary dynamics of speciation and extinction through time in Mesozoic dinosaurs, properly taking account of previously ignored statistical violations. We find overwhelming support for a long-term decline across all dinosaurs and within all three dinosaurian subclades (Ornithischia, Sauropodomorpha, and Theropoda), where speciation rate slowed down through time and was ultimately exceeded by extinction rate tens of millions of years before the K-Pg boundary. The only exceptions to this general pattern are the morphologically specialized herbivores, the Hadrosauriformes and Ceratopsidae, which show rapid species proliferations throughout the Late Cretaceous instead. Our results highlight that, despite some heterogeneity in speciation dynamics, dinosaurs showed a marked reduction in their ability to replace extinct species with new ones, making them vulnerable to extinction and unable to respond quickly to and recover from the final catastrophic event. PMID:27092007

Dinosaurs in decline tens of millions of years before their final extinction.

PubMed

Sakamoto, Manabu; Benton, Michael J; Venditti, Chris

2016-05-03

Whether dinosaurs were in a long-term decline or whether they were reigning strong right up to their final disappearance at the Cretaceous-Paleogene (K-Pg) mass extinction event 66 Mya has been debated for decades with no clear resolution. The dispute has continued unresolved because of a lack of statistical rigor and appropriate evolutionary framework. Here, for the first time to our knowledge, we apply a Bayesian phylogenetic approach to model the evolutionary dynamics of speciation and extinction through time in Mesozoic dinosaurs, properly taking account of previously ignored statistical violations. We find overwhelming support for a long-term decline across all dinosaurs and within all three dinosaurian subclades (Ornithischia, Sauropodomorpha, and Theropoda), where speciation rate slowed down through time and was ultimately exceeded by extinction rate tens of millions of years before the K-Pg boundary. The only exceptions to this general pattern are the morphologically specialized herbivores, the Hadrosauriformes and Ceratopsidae, which show rapid species proliferations throughout the Late Cretaceous instead. Our results highlight that, despite some heterogeneity in speciation dynamics, dinosaurs showed a marked reduction in their ability to replace extinct species with new ones, making them vulnerable to extinction and unable to respond quickly to and recover from the final catastrophic event.

Dinosaurs in decline tens of millions of years before their final extinction

NASA Astrophysics Data System (ADS)

Sakamoto, Manabu; Benton, Michael J.

2016-05-01

Whether dinosaurs were in a long-term decline or whether they were reigning strong right up to their final disappearance at the Cretaceous-Paleogene (K-Pg) mass extinction event 66 Mya has been debated for decades with no clear resolution. The dispute has continued unresolved because of a lack of statistical rigor and appropriate evolutionary framework. Here, for the first time to our knowledge, we apply a Bayesian phylogenetic approach to model the evolutionary dynamics of speciation and extinction through time in Mesozoic dinosaurs, properly taking account of previously ignored statistical violations. We find overwhelming support for a long-term decline across all dinosaurs and within all three dinosaurian subclades (Ornithischia, Sauropodomorpha, and Theropoda), where speciation rate slowed down through time and was ultimately exceeded by extinction rate tens of millions of years before the K-Pg boundary. The only exceptions to this general pattern are the morphologically specialized herbivores, the Hadrosauriformes and Ceratopsidae, which show rapid species proliferations throughout the Late Cretaceous instead. Our results highlight that, despite some heterogeneity in speciation dynamics, dinosaurs showed a marked reduction in their ability to replace extinct species with new ones, making them vulnerable to extinction and unable to respond quickly to and recover from the final catastrophic event.

Italian Contributions to the Development of Continuous Glucose Monitoring Sensors for Diabetes Management

PubMed Central

Sparacino, Giovanni; Zanon, Mattia; Facchinetti, Andrea; Zecchin, Chiara; Maran, Alberto; Cobelli, Claudio

2012-01-01

Monitoring glucose concentration in the blood is essential in the therapy of diabetes, a pathology which affects about 350 million people around the World (three million in Italy), causes more than four million deaths per year and consumes a significant portion of the budget of national health systems (10% in Italy). In the last 15 years, several sensors with different degree of invasiveness have been proposed to monitor glycemia in a quasi-continuous way (up to 1 sample/min rate) for relatively long intervals (up to 7 consecutive days). These continuous glucose monitoring (CGM) sensors have opened new scenarios to assess, off-line, the effectiveness of individual patient therapeutic plans from the retrospective analysis of glucose time-series, but have also stimulated the development of innovative on-line applications, such as hypo/hyper-glycemia alert systems and artificial pancreas closed-loop control algorithms. In this review, we illustrate some significant Italian contributions, both from industry and academia, to the growth of the CGM sensors research area. In particular, technological, algorithmic and clinical developments performed in Italy will be discussed and put in relation with the advances obtained in the field in the wider international research community. PMID:23202020

Italian contributions to the development of continuous glucose monitoring sensors for diabetes management.

PubMed

Sparacino, Giovanni; Zanon, Mattia; Facchinetti, Andrea; Zecchin, Chiara; Maran, Alberto; Cobelli, Claudio

2012-10-12

Monitoring glucose concentration in the blood is essential in the therapy of diabetes, a pathology which affects about 350 million people around the World (three million in Italy), causes more than four million deaths per year and consumes a significant portion of the budget of national health systems (10% in Italy). In the last 15 years, several sensors with different degree of invasiveness have been proposed to monitor glycemia in a quasi-continuous way (up to 1 sample/min rate) for relatively long intervals (up to 7 consecutive days). These continuous glucose monitoring (CGM) sensors have opened new scenarios to assess, off-line, the effectiveness of individual patient therapeutic plans from the retrospective analysis of glucose time-series, but have also stimulated the development of innovative on-line applications, such as hypo/hyper-glycemia alert systems and artificial pancreas closed-loop control algorithms. In this review, we illustrate some significant Italian contributions, both from industry and academia, to the growth of the CGM sensors research area. In particular, technological, algorithmic and clinical developments performed in Italy will be discussed and put in relation with the advances obtained in the field in the wider international research community.

Lymphoid cell kinetics under continuous low dose-rate gamma irradiation: A comparison study

NASA Technical Reports Server (NTRS)

Foster, B. R.

1975-01-01

A comparison study was conducted of the effects of continuous low dose-rate gamma irradiation on cell population kinetics of lymphoid tissue (white pulp) of the mouse spleen with findings as they relate to the mouse thymus. Experimental techniques employed included autoradiography and specific labeling with tritiated thymidine (TdR-(h-3)). The problem studied involved the mechanism of cell proliferation of lymphoid tissue of the mouse spleen and thymus under the stress of continuous irradiation at a dose rate of 10 roentgens (R) per day for 105 days (15 weeks). The aim was to determine whether or not a steady state or near-steady state of cell population could be established for this period of time, and what compensatory mechanisms of cell population were involved.

Perceived barriers to completing an e-learning program on evidence-based medicine.

PubMed

Gagnon, Marie-Pierre; Légaré, France; Labrecque, Michel; Frémont, Pierre; Cauchon, Michel; Desmartis, Marie

2007-01-01

The Continuing Professional Development Center of the Faculty of Medicine at Laval University offers an internet-based program on evidence-based medicine (EBM). After one year, only three physicians out of the 40 who willingly paid to register had completed the entire program. This descriptive study aimed to identify physicians' beliefs regarding their completion of this online program. Using theoretical concepts from the Theory of Planned Behaviour, a semi-structured telephone interview guide was developed to assess respondents' attitudes, perceived subjective norms, perceived obstacles and facilitating conditions with respect to completing this internet-based program. Three independent reviewers performed content analysis of the interview transcripts to obtain an appropriate level of reliability. Findings were shared and organised according to theoretical categories of beliefs. A total of 35 physicians (88% response rate) were interviewed. Despite perceived advantages to completing the internet-based program, barriers remained, especially those related to physicians' perceptions of time constraints. Lack of personal discipline and unfamiliarity with computers were also perceived as important barriers. This study offers a theoretical basis to understand physicians' beliefs towards completing an internet-based continuing medical education (CME) program on EBM. Based upon respondents' insights, several modifications were carried out to enhance the uptake of the program by physicians and, therefore, its implementation.

7 CFR 984.69 - Assessments.

Code of Federal Regulations, 2010 CFR

2010-01-01

... Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... marketing year. Each handler's pro rata share shall be the rate of assessment per kernelweight pound of... time during or after the marketing year the Secretary may increase the assessment rate as necessary to...

Prolonged remissions of metastatic breast cancer achieved with a six-drug regimen of relatively low toxicity.

PubMed

Hirshaut, Y; Kesselheim, H

1983-06-01

A combination of six chemotherapeutic agents was used to treat 30 women with unresectable metastatic carcinoma of the breast. In the first year five drugs (Cytoxan, methotrexate, 5-fluorouracil, vincristine, and prednisolone [CMFVP]) were given using a weekly schedule for administration of intravenous drugs. During the next year, a seven-week treatment cycle was introduced, with CMFVP given for four weeks, followed by an Adriamycin combination (Adriamycin, cyclophosphamide, and prednisone [ACP]) for three weeks and then the cycle repeated. Treatment was continued for three years or to time of relapse. Overall response rate was 66.7% (20/30). The median duration of response was 40 months and the median survival 39 months. Premenopausal women fared better than postmenopausal women with comparable response rates, duration of response and survival being 81.5%, 41 months, 56 months versus 50%, 20 months and 27 months. Of 16 premenopausal patients treated 7 achieved a complete response (CR) and, of these, 5 remained free of disease at 3 years. For these five individuals all treatment was then stopped. Disease recurred in two patients by five months but three remain disease-free after 43, 40 and 34 months, respectively without therapy. Toxicity was generally limited to heartburn and modest hair loss. This regimen appears to be more effective than those previously employed for metastatic breast cancer. However, comparative trials will be necessary to confirm its advantages.

Continuous in vitro evolution of catalytic function.

PubMed

Wright, M C; Joyce, G F

1997-04-25

A population of RNA molecules that catalyze the template-directed ligation of RNA substrates was made to evolve in a continuous manner in the test tube. A simple serial transfer procedure was used to achieve approximately 300 successive rounds of catalysis and selective amplification in 52 hours. During this time, the population size was maintained against an overall dilution of 3 x 10(298). Both the catalytic rate and amplification rate of the RNAs improved substantially as a consequence of mutations that accumulated during the evolution process. Continuous in vitro evolution makes it possible to maintain laboratory "cultures" of catalytic molecules that can be perpetuated indefinitely.

Continuous in vitro evolution of catalytic function

NASA Technical Reports Server (NTRS)

Wright, M. C.; Joyce, G. F.

1997-01-01

A population of RNA molecules that catalyze the template-directed ligation of RNA substrates was made to evolve in a continuous manner in the test tube. A simple serial transfer procedure was used to achieve approximately 300 successive rounds of catalysis and selective amplification in 52 hours. During this time, the population size was maintained against an overall dilution of 3 x 10(298). Both the catalytic rate and amplification rate of the RNAs improved substantially as a consequence of mutations that accumulated during the evolution process. Continuous in vitro evolution makes it possible to maintain laboratory "cultures" of catalytic molecules that can be perpetuated indefinitely.

First Responder Immersive Training Simulation Environment (FRITSE): Downwind Hazard Modeling of Scenarios

DTIC Science & Technology

2014-07-31

evaporating from the ground surface at a constant rate of 2.78 kg/s over 13 a period of 30 minutes, at which time all chlorine in the liquid pool would...caused 10,000 kg of chlorine to be expelled into the atmosphere in the form of vapor/aerosol droplets over a short time of 100 sec, at a release rate of...1,800 sec) at a constant rate of 5,000/1,800 =2.78 kg/s, at which time all chlorine in the liquid pool would have evaporated, and treated as “continuous

Three-dimensional compact explicit-finite difference time domain scheme with density variation

NASA Astrophysics Data System (ADS)

Tsuchiya, Takao; Maruta, Naoki

2018-07-01

In this paper, the density variation is implemented in the three-dimensional compact-explicit finite-difference time-domain (CE-FDTD) method. The formulation is first developed based on the continuity equation and the equation of motion, which include the density. Some numerical demonstrations are performed for the three-dimensional sound wave propagation in a two density layered medium. The numerical results are compared with the theoretical results to verify the proposed formulation.

Influence of PCR reagents on DNA polymerase extension rates measured on real-time PCR instruments.

PubMed

Montgomery, Jesse L; Wittwer, Carl T

2014-02-01

Radioactive DNA polymerase activity methods are cumbersome and do not provide initial extension rates. A simple extension rate assay would enable study of basic assumptions about PCR and define the limits of rapid PCR. A continuous assay that monitors DNA polymerase extension using noncovalent DNA dyes on common real-time PCR instruments was developed. Extension rates were measured in nucleotides per second per molecule of polymerase. To initiate the reaction, a nucleotide analog was heat activated at 95 °C for 5 min, the temperature decreased to 75 °C, and fluorescence monitored until substrate exhaustion in 30-90 min. The assay was linear with time for over 40% of the reaction and for polymerase concentrations over a 100-fold range (1-100 pmol/L). Extension rates decreased continuously with increasing monovalent cation concentrations (lithium, sodium, potassium, cesium, and ammonium). Melting-temperature depressors had variable effects. DMSO increased rates up to 33%, whereas glycerol had little effect. Betaine, formamide, and 1,2-propanediol decreased rates with increasing concentrations. Four common noncovalent DNA dyes inhibited polymerase extension. Heat-activated nucleotide analogs were 92% activated after 5 min, and hot start DNA polymerases were 73%-90% activated after 20 min. Simple DNA extension rate assays can be performed on real-time PCR instruments. Activity is decreased by monovalent cations, DNA dyes, and most melting temperature depressors. Rational inclusion of PCR components on the basis of their effects on polymerase extension is likely to be useful in PCR, particularly rapid-cycle or fast PCR.

Initial attitude determination for the hipparcos satellite

NASA Astrophysics Data System (ADS)

Van der Ha, Jozef C.

The present paper described the strategy and algorithms used during the initial on-ground three-axes attitude determination of ESA's astrometry satellite HIPPARCOS. The estimation is performed using calculated crossing times of identified stars over the Star Mapper's vertical and inclined slit systems as well as outputs from a set of rate-integrating gyros. Valid star transits in either of the two fields of view are expected to occur in average about every 30 s whereas the gyros are sampled at about 1 Hz. The state vector to be estimated consists of the three angles, three rates and three gyro drift rate components. Simulations have shown that convergence of the estimator is established within about 10 min and that the accuracies achieved are in the order of a few arcsec for the angles and a few milliarcsec per s for the rates. These stringent accuracies are in fact required for initialisation of subsequent autonomous on-board real-time attitude determination.

Product mass transfer resistance directly determined during freeze-drying cycle runs using tunable diode laser absorption spectroscopy (TDLAS) and pore diffusion model.

PubMed

Kuu, Wei Y; O'Bryan, Kevin R; Hardwick, Lisa M; Paul, Timothy W

2011-08-01

The pore diffusion model is used to express the dry layer mass transfer resistance, [Formula: see text], as a function of the ratio r(e)/?, where r(e) is the effective pore radius and ? is the tortuosity factor of the dry layer. Using this model, the effective pore radius of the dry layer can be estimated from the sublimation rate and product temperature profiles measured during primary drying. Freeze-drying cycle runs were performed using the LyoStar II dryer (FTS Systems), with real-time sublimation rate profiles during freeze drying continuously measured by tunable diode laser absorption spectroscopy (TDLAS). The formulations chosen for demonstration of the proposed approach include 5% mannitol, 5% sucrose, 5% lactose, 3% mannitol plus 2% sucrose, and a parenteral nutrition formulation denoted VitaM12. The three different methods used for determination of the product resistance are: (1) Using both the sublimation rate and product temperature profiles, (2) using the sublimation rate profile alone, and (3) using the product temperate profile alone. Unlike the second and third methods, the computation procedure of first method does not need solution of the complex heat and mass transfer equations.

Dynamical analyses of the time series for three foreign exchange rates

NASA Astrophysics Data System (ADS)

Kim, Sehyun; Kim, Soo Yong; Jung, Jae-Won; Kim, Kyungsik

2012-05-01

In this study, we investigate the multifractal properties of three foreign exchange rates (USD-KRW, USD-JPY, and EUR-USD) that are quoted with different economic scales. We estimate and analyze both the generalized Hurst exponent and the autocorrelation function in three foreign exchange rates. The USD-KRW is shown to have the strongest of the Hurst exponents when compared with the other two foreign exchange rates. In particular, the autocorrelation function of the USD-KRW has the largest memory behavior among three foreign exchange rates. It also exhibits a long-memory property in the first quarter, more than those in the other quarters.

[Support for Adult ASD in Medical Rework Program: Mutual Communication Program and Psychodrama].

PubMed

Yokoyama, Motonori

2015-01-01

While carrying out the Medical Rework Program, we realized the necessity for a supplementary medical treatment program aimed at adult ASD. Consequently, we started the Mutual Communication Program, which consists of standard SST and the new element of psychodrama. As a result, 32 participants have returned to their workplace in the three-year period, and the rate of successfully continuing to work was 93.8% at the time of the investigation. Various psychological tests also indicated significant improvement. In this article, we present a case study, explain psychodrama techniques employed in the program, and discuss their usefulness. The results suggest that psychodrama is a very effective assistive technique when the characteristics of ASD are taken into consideration.

Complementary therapy use and quality of life in persons with high-grade gliomas.

PubMed

Fox, Sherry; Laws, Edward R; Anderson, Frederick; Farace, Elana

2006-08-01

Studies have indicated that 30%-80% of cancer patients use complementary and alternative practices and products (CAPPs), but little is known about CAPPs use by persons with brain tumors. This secondary analysis of Glioma Outcomes Project data compared CAPPs users with nonusers, compared those who stopped using CAPPs with those who continued use, described frequency and patterns of CAPPs use, and compared the relationship of CAPPs use to self-reported quality of life (QOL) over time, in 186 persons with high-grade gliomas. CAPPs users at all three measurement points rated QOL higher, although not significantly higher, than nonusers. Study findings support further exploration of CAPPs use and its effects on key outcomes in persons with high-grade gliomas.

Revolving Loan Fund: A Novel Approach to Increasing Access to Long-Acting Reversible Contraception Methods in Community Health Centers.

PubMed

Evans, Megan L; Breeze, Janis L; Paulus, Jessica K; Meadows, Audra

The aim of this study was to assess the impact of a revolving loan fund (RLF) on timing of device insertion and long-acting reversible contraception (LARC) access among a high-risk urban population at 3 Boston community health centers. Three health centers were identified to implement a RLF. Each clinic received $5000 from the RLF to purchase LARC devices. Data collected through medical record review retrospectively 1 year prior to start of the RLF and prospectively for 1 year thereafter included patient demographics, type of LARC selected, patient's date of documented interest in a LARC device, and date of insertion. The effect of a RLF on delay to LARC insertion was tested using negative binomial regression, controlling for site and potential confounding variables between the pre- and post-RLF periods. Three urban community health centers. Reproductive-aged women who received family planning services at the 3 participating health centers. Increasing access to LARC and decreasing wait times to LARC insertion after implementation of the RLF. Data on 133 patients in the pre-RLF group and 205 in the post-RLF group were collected. There were no statistically significant differences in demographic or clinical characteristics between the 2 time periods. LARC uptake increased significantly from the pre- to post-RLF period, specifically among implant users. There was a statistically significant decrease in the mean number of days in delay from interest to insertion from the pre- to post-RLF period (pre-RLF: 31.3 ± 50.6 days; post-RLF: 13.6 ± 16.7 days, adjusted P < .001). The reasons for the delay did not differ significantly between the 2 time periods. The RLF decreased wait time for the devices and increased overall insertion rates. This may serve as a promising solution to improve LARC access in community health centers. This project could be expanded to include more health centers, creating a city wide RLF. This expansion could allow for further data analysis, including unintended pregnancy rates with LARC delay, LARC continuation rates, and sustainability of a RLF.

African Swine Fever in Uganda: Qualitative Evaluation of Three Surveillance Methods with Implications for Other Resource-Poor Settings.

PubMed

Chenais, Erika; Sternberg-Lewerin, Susanna; Boqvist, Sofia; Emanuelson, Ulf; Aliro, Tonny; Tejler, Emma; Cocca, Giampaolo; Masembe, Charles; Ståhl, Karl

2015-01-01

Animal diseases impact negatively on households and on national economies. In low-income countries, this pertains especially to socio-economic effects on household level. To control animal diseases and mitigate their impact, it is necessary to understand the epidemiology of the disease in its local context. Such understanding, gained through disease surveillance, is often lacking in resource-poor settings. Alternative surveillance methods have been developed to overcome some of the hurdles obstructing surveillance. The objective of this study was to evaluate and qualitatively compare three methods for surveillance of acute infectious diseases using African swine fever in northern Uganda as an example. Report-driven outbreak investigations, participatory rural appraisals (PRAs), and a household survey using a smartphone application were evaluated. All three methods had good disease-detecting capacity, and each of them detected many more outbreaks compared to those reported to the World Organization for Animal Health during the same time period. Apparent mortality rates were similar for the three methods although highest for the report-driven outbreak investigations, followed by the PRAs, and then the household survey. The three methods have different characteristics and the method of choice will depend on the surveillance objective. The optimal situation might be achieved by a combination of the methods: outbreak detection via smartphone-based real-time surveillance, outbreak investigation for collection of biological samples, and a PRA for a better understanding of the epidemiology of the specific outbreak. All three methods require initial investments and continuous efforts. The sustainability of the surveillance system should, therefore, be carefully evaluated before making such investments.

Case-based discussion supporting learning and practice in optometry.

PubMed

Bullock, Alison; Barnes, Emma; Ryan, Barbara; Sheen, Nik

2014-09-01

To enhance continuing professional development and address the risk that professional isolation poses, the UK General Optical Council introduced a requirement for all optometrists to engage in at least one case-based discussion per 3 year cycle of continuing education. In this paper, we explore participants' impression of the acceptability, effectiveness and long-term impact-on-practice of case-based discussion as a mode of continuing education. Case-based discussion participants attended an evening session comprising a lecture and a group discussion. They completed three questionnaires: prior to the session, immediately post-session and 3-4 months post-session. We coded the questionnaires to allow matching. Seventy-five case-based discussion groups were held with 379 participants; 377 completed both pre- and post-questionnaires and 331 (88%) returned a follow-up questionnaire. Case-based discussions were an acceptable method of learning, with many preferring it to distance-learning. Prior to the event, women, employees and part-time workers were more likely to have concerns about participating. In terms of learning, gaps in knowledge were more likely to be revealed in those who work in isolation. The respondents highlighted social aspects, reassurance of practice as well as new learning. Participants significantly improved self-confidence ratings in all key learning areas. At three months post-session, the majority (75%) self-reported that they had implemented their intended changes to practice. The evaluation showed that participants felt that case-based discussion developed their knowledge, notably for sole practitioners, and influenced later workplace practice. The peer interaction of this mode of continuing education can combat professional isolation. © 2014 The Authors Ophthalmic & Physiological Optics © 2014 The College of Optometrists.

Comparison of continuous versus categorical tumor measurement-based metrics to predict overall survival in cancer treatment trials.

PubMed

An, Ming-Wen; Mandrekar, Sumithra J; Branda, Megan E; Hillman, Shauna L; Adjei, Alex A; Pitot, Henry C; Goldberg, Richard M; Sargent, Daniel J

2011-10-15

The categorical definition of response assessed via the Response Evaluation Criteria in Solid Tumors has documented limitations. We sought to identify alternative metrics for tumor response that improve prediction of overall survival. Individual patient data from three North Central Cancer Treatment Group trials (N0026, n = 117; N9741, n = 1,109; and N9841, n = 332) were used. Continuous metrics of tumor size based on longitudinal tumor measurements were considered in addition to a trichotomized response [TriTR: response (complete or partial) vs. stable disease vs. progression). Cox proportional hazards models, adjusted for treatment arm and baseline tumor burden, were used to assess the impact of the metrics on subsequent overall survival, using a landmark analysis approach at 12, 16, and 24 weeks postbaseline. Model discrimination was evaluated by the concordance (c) index. The overall best response rates for the three trials were 26%, 45%, and 25%, respectively. Although nearly all metrics were statistically significantly associated with overall survival at the different landmark time points, the concordance indices (c-index) for the traditional response metrics ranged from 0.59 to 0.65; for the continuous metrics from 0.60 to 0.66; and for the TriTR metrics from 0.64 to 0.69. The c-indices for TriTR at 12 weeks were comparable with those at 16 and 24 weeks. Continuous tumor measurement-based metrics provided no predictive improvement over traditional response-based metrics or TriTR; TriTR had better predictive ability than best TriTR or confirmed response. If confirmed, TriTR represents a promising endpoint for future phase II trials. ©2011 AACR.

Comparison of continuous versus categorical tumor measurement-based metrics to predict overall survival in cancer treatment trials

PubMed Central

An, Ming-Wen; Mandrekar, Sumithra J.; Branda, Megan E.; Hillman, Shauna L.; Adjei, Alex A.; Pitot, Henry; Goldberg, Richard M.; Sargent, Daniel J.

2011-01-01

Purpose The categorical definition of response assessed via the Response Evaluation Criteria in Solid Tumors has documented limitations. We sought to identify alternative metrics for tumor response that improve prediction of overall survival. Experimental Design Individual patient data from three North Central Cancer Treatment Group trials (N0026, n=117; N9741, n=1109; N9841, n=332) were used. Continuous metrics of tumor size based on longitudinal tumor measurements were considered in addition to a trichotomized response (TriTR: Response vs. Stable vs. Progression). Cox proportional hazards models, adjusted for treatment arm and baseline tumor burden, were used to assess the impact of the metrics on subsequent overall survival, using a landmark analysis approach at 12-, 16- and 24-weeks post baseline. Model discrimination was evaluated using the concordance (c) index. Results The overall best response rates for the three trials were 26%, 45%, and 25% respectively. While nearly all metrics were statistically significantly associated with overall survival at the different landmark time points, the c-indices for the traditional response metrics ranged from 0.59-0.65; for the continuous metrics from 0.60-0.66 and for the TriTR metrics from 0.64-0.69. The c-indices for TriTR at 12-weeks were comparable to those at 16- and 24-weeks. Conclusions Continuous tumor-measurement-based metrics provided no predictive improvement over traditional response based metrics or TriTR; TriTR had better predictive ability than best TriTR or confirmed response. If confirmed, TriTR represents a promising endpoint for future Phase II trials. PMID:21880789

Hydraulic fracture monitoring in hard rock at 410 m depth with an advanced fluid-injection protocol and extensive sensor array

NASA Astrophysics Data System (ADS)

Zang, Arno; Stephansson, Ove; Stenberg, Leif; Plenkers, Katrin; Specht, Sebastian; Milkereit, Claus; Schill, Eva; Kwiatek, Grzegorz; Dresen, Georg; Zimmermann, Günter; Dahm, Torsten; Weber, Michael

2017-02-01

In this paper, an underground experiment at the Äspö Hard Rock Laboratory (HRL) is described. Main goal is optimizing geothermal heat exchange in crystalline rock mass at depth by multistage hydraulic fracturing with minimal impact on the environment, that is, seismic events. For this, three arrays with acoustic emission, microseismicity and electromagnetic sensors are installed mapping hydraulic fracture initiation and growth. Fractures are driven by three different water injection schemes (continuous, progressive and pulse pressurization). After a brief review of hydraulic fracture operations in crystalline rock mass at mine scale, the site geology and the stress conditions at Äspö HRL are described. Then, the continuous, single-flow rate and alternative, multiple-flow rate fracture breakdown tests in a horizontal borehole at depth level 410 m are described together with the monitoring networks and sensitivity. Monitoring results include the primary catalogue of acoustic emission hypocentres obtained from four hydraulic fractures with the in situ trigger and localizing network. The continuous versus alternative water injection schemes are discussed in terms of the fracture breakdown pressure, the fracture pattern from impression packer result and the monitoring at the arrays. An example of multistage hydraulic fracturing with several phases of opening and closing of fracture walls is evaluated using data from acoustic emissions, seismic broad-band recordings and electromagnetic signal response. Based on our limited amount of in situ tests (six) and evaluation of three tests in Ävrö granodiorite, in the multiple-flow rate test with progressively increasing target pressure, the acoustic emission activity starts at a later stage in the fracturing process compared to the conventional fracturing case with continuous water injection. In tendency, also the total number and magnitude of acoustic events are found to be smaller in the progressive treatment with frequent phases of depressurization.

Opportunities to improve the conversion of food waste to lactate: Fine-tuning secondary factors.

PubMed

RedCorn, Raymond; Engelberth, Abigail S

2017-11-01

Extensive research has demonstrated the potential for bioconversion of food waste to lactate, with major emphasis on adjusting temperature, pH, and loading rate of the fermentation. Each of these factors has a significant effect on lactate production; however, additional secondary factors have received little attention. Here we investigate three additional factors where opportunities exist for process improvement: freezing of samples during storage, discontinuous pH control, and holdover of fermentation broth between fermentations. Freezing samples prior to fermentation was shown to reduce the production rate of lactate by 8%, indicating freeze-thaw should be avoided in experiments. Prior work indicated a trade-off in pH control strategies, where discontinuous pH control correlated with higher lactate accumulation while continuous pH control correlated with higher production rate. Here we demonstrate that continuous pH control can achieve both higher lactate accumulation and higher production rate. Finally, holding over fermentation broth was shown to be a simple method to improve production rate (by 18%) at high food waste loading rates (>140 g volatile solids L -1 ) but resulted in lower lactate accumulation (by 17%). The results inform continued process improvements within the waste treatment of food waste through fermentation to lactic acid.

Identifying heterogeneity in rates of morphological evolution: discrete character change in the evolution of lungfish (Sarcopterygii; Dipnoi).

PubMed

Lloyd, Graeme T; Wang, Steve C; Brusatte, Stephen L

2012-02-01

Quantifying rates of morphological evolution is important in many macroevolutionary studies, and critical when assessing possible adaptive radiations and episodes of punctuated equilibrium in the fossil record. However, studies of morphological rates of change have lagged behind those on taxonomic diversification, and most authors have focused on continuous characters and quantifying patterns of morphological rates over time. Here, we provide a phylogenetic approach, using discrete characters and three statistical tests to determine points on a cladogram (branches or entire clades) that are characterized by significantly high or low rates of change. These methods include a randomization approach that identifies branches with significantly high rates and likelihood ratio tests that pinpoint either branches or clades that have significantly higher or lower rates than the pooled rate of the remainder of the tree. As a test case for these methods, we analyze a discrete character dataset of lungfish, which have long been regarded as "living fossils" due to an apparent slowdown in rates since the Devonian. We find that morphological rates are highly heterogeneous across the phylogeny and recover a general pattern of decreasing rates along the phylogenetic backbone toward living taxa, from the Devonian until the present. Compared with previous work, we are able to report a more nuanced picture of lungfish evolution using these new methods. © 2011 The Author(s). Evolution© 2011 The Society for the Study of Evolution.

Identification and Reconfigurable Control of Impaired Multi-Rotor Drones

NASA Technical Reports Server (NTRS)

Stepanyan, Vahram; Krishnakumar, Kalmanje; Bencomo, Alfredo

2016-01-01

The paper presents an algorithm for control and safe landing of impaired multi-rotor drones when one or more motors fail simultaneously or in any sequence. It includes three main components: an identification block, a reconfigurable control block, and a decisions making block. The identification block monitors each motor load characteristics and the current drawn, based on which the failures are detected. The control block generates the required total thrust and three axis torques for the altitude, horizontal position and/or orientation control of the drone based on the time scale separation and nonlinear dynamic inversion. The horizontal displacement is controlled by modulating the roll and pitch angles. The decision making algorithm maps the total thrust and three torques into the individual motor thrusts based on the information provided by the identification block. The drone continues the mission execution as long as the number of functioning motors provide controllability of it. Otherwise, the controller is switched to the safe mode, which gives up the yaw control, commands a safe landing spot and descent rate while maintaining the horizontal attitude.

Physiological evaluation of men wearing three different toxicological protective systems

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

Levine, L.; Cadarette, B.S.; Sawka, M.N.

1989-08-01

This study examined the physiological responses of seven volunteers exercising in the heat while wearing three different toxicological protective systems. The Toxicological Agent Protective (TAP) suit has been available for use for more than 30 years while the other two protective systems are developmental efforts. The Self-Contained Toxicological Environmental Protection Outfit (STEPO) includes either a backpack-rebreather (with CO{sub 2} scrubber) and ice-cooling vest (STEPO-R), or a tether system which supplies breathing/cooling air inside the suit (STEPO-T). After the volunteers were heat acclimated, the three toxicological protection systems were evaluated utilizing a counter-balanced experimental design initially in a hot and thenmore » in a cool environment while subjects walked at 1.12 m/s, 0% grade for an attempted two hours. There was no statistical advantage of any one system in terms of exercise time in the cool environment. While evaporated sweating rate was greater for the STEPO-T in the cool environment compared to both STEPO-R and TAP. Development efforts to improve the STEPO system designs continue, and physiological evaluation of new developmental models is underway.« less

Bronchoscopic Implantation of a Novel Wireless Electromagnetic Transponder in the Canine Lung: A Feasibility Study

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

Mayse, Martin L.; Parikh, Parag J.; Lechleiter, Kristen M.

2008-09-01

Purpose: The success of targeted radiation therapy for lung cancer treatment is limited by tumor motion during breathing. A real-time, objective, nonionizing, electromagnetic localization system using implanted electromagnetic transponders has been developed (Beacon electromagnetic transponder, Calypso Medical Technologies, Inc., Seattle, WA). We evaluated the feasibility and fixation of electromagnetic transponders bronchoscopically implanted in small airways of canine lungs and compared to results using gold markers. Methods and Materials: After approval of the Animal Studies Committee, five mongrel dogs were anesthetized, intubated, and ventilated. Three transponders were inserted into the tip of a plastic catheter, passed through the working channel ofmore » a flexible bronchoscope, and implanted into small airways of a single lobe using fluoroscopic guidance. This procedure was repeated for three spherical gold markers in the opposite lung. One, 7, 14, 28, and 60 days postimplantation imaging was used to assess implant fixation. Results: Successful bronchoscopic implantation was possible for 15 of 15 transponders and 12 of 15 gold markers; 3 markers were deposited in the pleural space. Fixation at 1 day was 15 of 15 for transponders and 12 of 12 for gold markers. Fixation at 60 days was 6 of 15 for transponders and 7 of 12 for gold markers, p value = 0.45. Conclusions: Bronchoscopic implantation of both transponders and gold markers into the canine lung is feasible, but fixation rates are low. If fixation rates can be improved, implantable electromagnetic transponders may allow improved radiation therapy for lung cancer by providing real-time continuous target tracking. Developmental work is under way to improve the fixation rates and to reduce sensitivity to implantation technique.« less

Development of a questionnaire encompassing indicators of distress: a tool for use with women in surgical continuity of care for breast cancer.

PubMed

Jørgensen, L; Garne, J P; Søgaard, M; Laursen, B S

2015-04-01

Women with breast cancer often experience significant distress. Currently, there are no questionnaires aimed at identifying women's unique and possible changing indicators for distress in surgical continuity of care for breast cancer. We developed and tested three questionnaires specifically for this use. We first searched PubMed, CINAHL and PsycINFO to retrieve information on previously described indicators. Next, we conducted a focus group interview with 6 specialised nurses, who have extensive experience about consequences of breast cancer for women in surgical continuity of care. The questionnaire was tested on 18 women scheduled for breast cancer surgery. Subsequently, the women were debriefed to gain knowledge about comprehensibility, readability and relevance of items, and the time needed to complete the questionnaire. After adjustment, the questionnaires were field-tested concomitantly with a clinical study, which both consisted of a survey and an interview study. Three multi-item questionnaires were developed specific to different time points in surgical continuity of care. The questionnaires share a core of statements divided into seven sub-scales: emotional and physical situation, social condition, sexuality, body image, religion and organisational factors. Besides the core of statements, each questionnaire has different statements depending on the time point of surgical continuity of care when it was to be responded to. The questionnaires contain comprehensive items that can identify indicators for distress in individual women taking part in surgical continuity of care. The items were understandable and the time used for filling in the questionnaires was reasonable. Copyright © 2014 Elsevier Ltd. All rights reserved.

Randomized trial of short-course radiotherapy versus long-course chemoradiation comparing rates of local recurrence in patients with T3 rectal cancer: Trans-Tasman Radiation Oncology Group trial 01.04.

PubMed

Ngan, Samuel Y; Burmeister, Bryan; Fisher, Richard J; Solomon, Michael; Goldstein, David; Joseph, David; Ackland, Stephen P; Schache, David; McClure, Bev; McLachlan, Sue-Anne; McKendrick, Joseph; Leong, Trevor; Hartopeanu, Cris; Zalcberg, John; Mackay, John

2012-11-01

To compare the local recurrence (LR) rate between short-course (SC) and long-course (LC) neoadjuvant radiotherapy for rectal cancer. Eligible patients had ultrasound- or magnetic resonance imaging-staged T3N0-2M0 rectal adenocarcinoma within 12 cm from anal verge. SC consisted of pelvic radiotherapy 5 × 5 Gy in 1 week, early surgery, and six courses of adjuvant chemotherapy. LC was 50.4 Gy, 1.8 Gy/fraction, in 5.5 weeks, with continuous infusional fluorouracil 225 mg/m(2) per day, surgery in 4 to 6 weeks, and four courses of chemotherapy. Three hundred twenty-six patients were randomly assigned; 163 patients to SC and 163 to LC. Median potential follow-up time was 5.9 years (range, 3.0 to 7.8 years). Three-year LR rates (cumulative incidence) were 7.5% for SC and 4.4% for LC (difference, 3.1%; 95% CI, -2.1 to 8.3; P = .24). For distal tumors (< 5 cm), six of 48 SC patients and one of 31 LC patients experienced local recurrence (P = .21). Five-year distant recurrence rates were 27% for SC and 30% for LC (log-rank P = 0.92; hazard ratio [HR] for LC:SC, 1.04; 95% CI, 0.69 to 1.56). Overall survival rates at 5 years were 74% for SC and 70% for LC (log-rank P = 0.62; HR, 1.12; 95% CI, 0.76 to 1.67). Late toxicity rates were not substantially different (Radiation Therapy Oncology Group/European Organisation for Research and Treatment of Cancer G3-4: SC, 5.8%; LC, 8.2%; P = .53). Three-year LR rates between SC and LC were not statistically significantly different; the CI for the difference is consistent with either no clinically important difference or differences in favor of LC. LC may be more effective in reducing LR for distal tumors. No differences in rates of distant recurrence, relapse-free survival, overall survival, or late toxicity were detected.

[Study on extraction process of zhanjin ruji].

PubMed

Du, Zhi-qian; Du, Tian-xin; Wang, Zhong-dong; Li, Gen-lin

2003-01-01

To select the optimum extraction process of Zhanjin Ruji. To observe influence of extraction time upon the extraction rate of volatile oil, the orthogonal test was adopted to observe the extraction process by alcohol from the extraction rate and content of the total saponins in Radix Notoginseng. The three kinds of herbs including Radix Angelicae Sinensis, Resina Olibani and Myrrha were extracted with water for 3 hours, 95% of volatile oil can be distilled. The three kinds of herbs including Radix Notoginseng, Herba Lycopodii and Radix Gentianae Macrophyllac were extracted by alcohol. Four factors such as alcohol concentration(A), extraction times(B), extraction time(C), and solvent amount(D), had not significant effect on the content of total saponins in Radix Notoginseng in herbal extraction, but factor A and B had significant effect on the extraction rate. The optimum extraction process was as follows extracted with 5 times the amount of the solvent volum 60% alcohol for 3 times and with each time for 1 hour. Three times experiments showed that the extraction rate was 26.5% and the content of the total saponins in Radix Notoginseng was 17.28% mg.g-1. The above experimental results can provide experimental basis for deciding the extraction process of Zhanjin Ruji.

Short-term results of a prospective randomized evaluator blinded multicenter study comparing TVT and TVT-Secur.

PubMed

Andrada Hamer, Maria; Larsson, Per-Göran; Teleman, Pia; Etén-Bergqvist, Christina; Persson, Jan

2011-07-01

The aim of this prospective randomized multicenter study was to compare TVT (tension-free vaginal tape) with TVT-Secur in terms of efficacy and safety. We set out to enrol 280 stress incontinent women with a half time interim analysis of short-term cure and a continuous registration of adverse events. Of 133 randomized women, 126 were operated and 123 (TVT n = 62, TVT-Secur n = 61) available for 2 months follow-up. No significant differences were found between groups regarding demographics or grade of incontinence. At 2 months follow-up, subjective cure rate following TVT-Secur was significantly lower than for TVT (72% and 92%, respectively, p = 0.01). Three major complications occurred in the TVT-Secur group: tape erosion into the urethra, a tape inadvertently placed inside the bladder, and an immediate postoperative bleeding from the corona mortis. No major complications occurred in the TVT group. No significant differences were found between groups regarding perioperative bleeding, hospital stay, urge symptoms, or postoperative urinary tract infections. Median time for surgery was 13 and 22 min for TVT-Secur and TVT, respectively (p < 0.0001). In a prospective randomized controlled study, the TVT-Secur procedure had a significantly lower subjective cure rate than the retropubic TVT procedure. Due to this, in addition to three serious complications in the TVT-Secur group, we decided to stop further enrolment after the interim analysis. We discourage from further use of the TVT-Secur.

Dysrhythmia of timed movements in Parkinson's disease and freezing of gait.

PubMed

Tolleson, Christopher M; Dobolyi, David G; Roman, Olivia C; Kanoff, Kristen; Barton, Scott; Wylie, Scott A; Kubovy, Michael; Claassen, Daniel O

2015-10-22

A well-established motor timing paradigm, the Synchronization-Continuation Task (SCT), quantifies how accurately participants can time finger tapping to a rhythmic auditory beat (synchronization phase) then maintain this rhythm after the external auditory cue is extinguished, where performance depends on an internal representation of the beat (continuation phase). In this study, we investigated the hypothesis that Parkinson's disease (PD) patients with clinical symptoms of freezing of gait (FOG) exhibit exaggerated motor timing deficits. We predicted that dysrhythmia is exacerbated when finger tapping is stopped temporarily and then reinitiated under the guidance of an internal representation of the beat. Healthy controls and PD patients with and without FOG performed the SCT with and without the insertion of a 7-s cessation of motor tapping between synchronization and continuation phases. With no interruption between synchronization and continuation phases, PD patients, especially those with FOG, showed pronounced motor timing hastening at the slowest inter-stimulus intervals during the continuation phase. The introduction of a gap prior to the continuation phase had a beneficial effect for healthy controls and PD patients without FOG, although patients with FOG continued to show pronounced and persistent motor timing hastening. Ratings of freezing of gait severity across the entire sample of PD tracked closely with the magnitude of hastening during the continuation phase. These results suggest that PD is accompanied by a unique dysrhythmia of measured movements, with FOG reflecting a particularly pronounced disruption to internal rhythmic timing. Copyright © 2015 Elsevier B.V. All rights reserved.

Measuring Competence and Dysfunction in Preschool Children: Source Agreement and Component Structure

ERIC Educational Resources Information Center

Klyce, Daniel; Conger, Anthony J.; Conger, Judith Cohen; Dumas, Jean E.

2011-01-01

Agreement between parents and teachers on ratings of three domains of behaviors exhibited by preschool children and the structural relations between these domains were measured. Parents and teachers rated the behaviors of a socioeconomically diverse sample of 610 children; ratings were obtained from parents at three time points and from teachers…