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Sample records for coupled pacing improves

  1. Reduction of pacing output coupling capacitance for sensing the evoked response.

    PubMed

    Sperzel, J; Neuzner, J; Schwarz, T; Zhu, Q; König, A; Kay, G N

    2001-09-01

    Sensing of the intracardiac evoked response (ER) after a pacing stimulus has been used in implantable pacemakers for automatic verification of capture. Reliable detection of ER is hampered by large residual afterpotentials associated with pacing stimuli. This led to the development of various technological solutions, like the use of triphasic pacing pulses and low polarizing electrode systems. This study investigated the effect of reducing the coupling capacitance (CC) in the pacemaker output circuitry on the magnitude of afterpotential, and the ability to automate detection of ventricular evoked response. A CC of 2.2 microF and four different blanking and recharge time settings were clinically tested to evaluate its impact on sensing of the ventricular ER and pacing threshold. Using an automatic step-down threshold algorithm, 54 consecutive patients, aged 70 +/- 10 years with acutely (n = 27) or chronically (n = 27) implanted ventricular pacing leads were enrolled for measurement testing. Routine measurements, using a standard pacing system analyzer (PSA), were (mean +/- SD) impedance 569 +/- 155 omega, R wave amplitude baseline to peak 9.8 +/- 3.7 mV and threshold 0.9 +/- 0.7 V at 0.4-ms pulse width. This new capture verification scheme, based on a CC of 2.2 microF and recharge/blanking timing setting of 10/12 ms, was successful in 52 patients which is equivalent to a success rate of 96%. In a subgroup of 26 patients implanted with bipolar ventricular leads (10 chronic, 16 acute), data were collected in unipolar (UP) and bipolar (BP) pace/sense configurations. Also, ER signals were recorded with two different band-pass filters: a wider band (WB) of 6-250 Hz and a conventional narrow band (NB) of 20-100 Hz. WB sensing from UP lead configuration yielded statistically significant larger signal to artifact ratios (SAR) than the other settings (P < 0.01). A dedicated unipolar ER sensing configuration using a small output capacitor and a wider band-pass filter enables

  2. Improvement of Right Ventricular Hemodynamics with Left Ventricular Endocardial Pacing during Cardiac Resynchronization Therapy

    PubMed Central

    HYDE, EOIN R.; BEHAR, JONATHAN M.; CROZIER, ANDREW; CLARIDGE, SIMON; JACKSON, TOM; SOHAL, MANAV; GILL, JASWINDER S.; O'NEILL, MARK D.; RAZAVI, REZA; RINALDI, CHRISTOPHER A.

    2016-01-01

    Background Cardiac resynchronization therapy (CRT) with biventricular epicardial (BV‐CS) or endocardial left ventricular (LV) stimulation (BV‐EN) improves LV hemodynamics. The effect of CRT on right ventricular function is less clear, particularly for BV‐EN. Our objective was to compare the simultaneous acute hemodynamic response (AHR) of the right and left ventricles (RV and LV) with BV‐CS and BV‐EN in order to determine the optimal mode of CRT delivery. Methods Nine patients with previously implanted CRT devices successfully underwent a temporary pacing study. Pressure wires measured the simultaneous AHR in both ventricles during different pacing protocols. Conventional epicardial CRT was delivered in LV‐only (LV‐CS) and BV‐CS configurations and compared with BV‐EN pacing in multiple locations using a roving decapolar catheter. Results Best BV‐EN (optimal AHR of all LV endocardial pacing sites) produced a significantly greater RV AHR compared with LV‐CS and BV‐CS pacing (P < 0.05). RV AHR had a significantly increased standard deviation compared to LV AHR (P < 0.05) with a weak correlation between RV and LV AHR (Spearman rs = −0.06). Compromised biventricular optimization, whereby RV AHR was increased at the expense of a smaller decrease in LV AHR, was achieved in 56% of cases, all with BV‐EN pacing. Conclusions BV‐EN pacing produces significant increases in both LV and RV AHR, above that achievable with conventional epicardial pacing. RV AHR cannot be used as a surrogate for optimizing LV AHR; however, compromised biventricular optimization is possible. The beneficial effect of endocardial LV pacing on RV function may have important clinical benefits beyond conventional CRT. PMID:27001004

  3. A Fast-Start Pacing Strategy Speeds Pulmonary Oxygen Uptake Kinetics and Improves Supramaximal Running Performance

    PubMed Central

    Turnes, Tiago; Salvador, Amadeo Félix; Lisbôa, Felipe Domingos; de Aguiar, Rafael Alves; Cruz, Rogério Santos de Oliveira; Caputo, Fabrizio

    2014-01-01

    The focus of the present study was to investigate the effects of a fast-start pacing strategy on running performance and pulmonary oxygen uptake () kinetics at the upper boundary of the severe-intensity domain. Eleven active male participants (28±10 years, 70±5 kg, 176±6 cm, 57±4 mL/kg/min) visited the laboratory for a series of tests that were performed until exhaustion: 1) an incremental test; 2) three laboratory test sessions performed at 95, 100 and 110% of the maximal aerobic speed; 3) two to four constant speed tests for the determination of the highest constant speed (HS) that still allowed achieving maximal oxygen uptake; and 4) an exercise based on the HS using a higher initial speed followed by a subsequent decrease. To predict equalized performance values for the constant pace, the relationship between time and distance/speed through log-log modelling was used. When a fast-start was utilized, subjects were able to cover a greater distance in a performance of similar duration in comparison with a constant-pace performance (constant pace: 670 m±22%; fast-start: 683 m±22%; P = 0.029); subjects also demonstrated a higher exercise tolerance at a similar average speed when compared with constant-pace performance (constant pace: 114 s±30%; fast-start: 125 s±26%; P = 0.037). Moreover, the mean response time was reduced after a fast start (constant pace: 22.2 s±28%; fast-start: 19.3 s±29%; P = 0.025). In conclusion, middle-distance running performances with a duration of 2–3 min are improved and response time is faster when a fast-start is adopted. PMID:25360744

  4. Efficacy of paced breathing for insomnia: enhances vagal activity and improves sleep quality.

    PubMed

    Tsai, H J; Kuo, Terry B J; Lee, Guo-She; Yang, Cheryl C H

    2015-03-01

    Fourteen self-reported insomniacs (SRI) and 14 good sleepers (GS) had their cardiac neuronal activity assessed by heart rate variability (HRV) under controlled respiration at a slow frequency rate of 0.1 Hz, and a forced rate of 0.2 Hz during daytime rest. Nighttime sleep was measured by polysomnography. The SRI showed depressed high frequency power of HRV compared to the GS. An increased total power of HRV was observed among the SRI during slow, paced breathing compared with spontaneous breathing and 0.2 Hz. Sleep onset latency, number of awakenings, and awakening time during sleep were decreased and sleep efficiency was increased if SRI practiced slow, paced breathing exercises for 20 min before going to sleep. Our results indicate that there is autonomic dysfunction among insomniacs, especially in relation to vagal activity; however, this decreased vagal activity can be facilitated by practicing slow, paced breathing, thereby improving sleep quality. PMID:25234581

  5. "U-Pace" Instruction: Improving Student Success by Integrating Content Mastery and Amplified Assistance

    ERIC Educational Resources Information Center

    Reddy, Diane M.; Pfeiffer, Heidi M.; Fleming, Raymond; Ports, Katie A.; Pedrick, Laura E.; Barnack-Tavlaris, Jessica L.; Jirovec, Danielle L.; Helion, Alicia M.; Swain, Rodney A.

    2013-01-01

    "U-Pace," an instructional intervention, has potential for widespread implementation because student behavior recorded in any learning management system is used by "U-Pace" instructors to tailor coaching of student learning based on students' strengths and motivations. "U-Pace" utilizes an online learning…

  6. "U-Pace" Instruction: Improving Student Success by Integrating Content Mastery and Amplified Assistance

    ERIC Educational Resources Information Center

    Reddy, Diane M.; Pfeiffer, Heidi M.; Fleming, Raymond; Ports, Katie A.; Pedrick, Laura E.; Barnack-Tavlaris, Jessica L.; Jirovec, Danielle L.; Helion, Alicia M.; Swain, Rodney A.

    2013-01-01

    "U-Pace," an instructional intervention, has potential for widespread implementation because student behavior recorded in any learning management system is used by "U-Pace" instructors to tailor coaching of student learning based on students' strengths and motivations. "U-Pace" utilizes an online learning environment to integrate content mastery…

  7. Muscle ischemic preconditioning does not improve performance during self-paced exercise.

    PubMed

    Tocco, F; Marongiu, E; Ghiani, G; Sanna, I; Palazzolo, G; Olla, S; Pusceddu, M; Sanna, P; Corona, F; Concu, A; Crisafulli, A

    2015-01-01

    Muscle ischemic preconditioning (IP) has been found to improve exercise performance in laboratory tests. This investigation aims at verifying whether performance is improved by IP during self-paced exercise (SPE) in the field. 11 well-trained male runners performed 3 randomly assigned 5 000 m self-paced running tests on an outdoor track. One was the reference (RT) test, while the others were performed following muscle IP (IPT) and a control sham test (ST). Average speeds were measured during each test. Mean values in oxygen uptake (VO2), aerobic energy cost (AEC) during race and post-race blood lactate (BLa) were gathered. Data showed that none of the studied variables were affected by IPT or ST with respect to the RT test. Average speeds were 4.63±0.31, 4.62±0.31 and 4.60±0.25 m·s(-1) for the RT, the ST and the IPT tests, respectively. Moreover, there was no difference among tests in speed reached during each lap. VO2 was 3.5±0.69, 3.74±0.85 and 3.62±1.19 l·min(-1). AEC was 1.04±0.15, 1.08±0.1 and 1.09±0.15 kcal·kg(-1)·km(-1). Finally, post-race BLa levels reached 12.85±3.54, 11.88±4.74 and 12.82±3.6 mmol·l(-1). These findings indicate that performance during SPE is not ameliorated by ischemic preconditioning, thereby indicating that IP is not suitable as an ergogenic aid. PMID:25264861

  8. In Heart Failure Patients with Left Bundle Branch Block Single Lead MultiSpot Left Ventricular Pacing Does Not Improve Acute Hemodynamic Response To Conventional Biventricular Pacing. A Multicenter Prospective, Interventional, Non-Randomized Study

    PubMed Central

    Sterliński, Maciej; Sokal, Adam; Lenarczyk, Radosław; Van Heuverswyn, Frederic; Rinaldi, C. Aldo; Vanderheyden, Marc; Khalameizer, Vladimir; Francis, Darrel; Heynens, Joeri; Stegemann, Berthold; Cornelussen, Richard

    2016-01-01

    Introduction Recent efforts to increase CRT response by multiSPOT pacing (MSP) from multiple bipols on the same left ventricular lead are still inconclusive. Aim The Left Ventricular (LV) MultiSPOTpacing for CRT (iSPOT) study compared the acute hemodynamic response of MSP pacing by using 3 electrodes on a quadripolar lead compared with conventional biventricular pacing (BiV). Methods Patients with left bundle branch block (LBBB) underwent an acute hemodynamic study to determine the %change in LV+dP/dtmax from baseline atrial pacing compared to the following configurations: BiV pacing with the LV lead in a one of lateral veins, while pacing from the distal, mid, or proximal electrode and all 3 electrodes together (i.e. MSP). All measurements were repeated 4 times at 5 different atrioventricular delays. We also measured QRS-width and individual Q-LV durations. Results Protocol was completed in 24 patients, all with LBBB (QRS width 171±20 ms) and 58% ischemic aetiology. The percentage change in LV+dP/dtmax for MSP pacing was 31.0±3.3% (Mean±SE), which was not significantly superior to any BiV pacing configuration: 28.9±3.2% (LV-distal), 28.3±2.7% (LV-mid), and 29.5±3.0% (LV-prox), respectively. Correlation between LV+dP/dtmax and either QRS-width or Q-LV ratio was poor. Conclusions In patients with LBBB MultiSPOT LV pacing demonstrated comparable improvement in contractility to best conventional BiV pacing. Optimization of atrioventricular delay is important for the best performance for both BiV and MultiSPOT pacing configurations. Trial Registration ClinicalTrials.gov NTC01883141 PMID:27124724

  9. Gpr176 is a Gz-linked orphan G-protein-coupled receptor that sets the pace of circadian behaviour

    PubMed Central

    Doi, Masao; Murai, Iori; Kunisue, Sumihiro; Setsu, Genzui; Uchio, Naohiro; Tanaka, Rina; Kobayashi, Sakurako; Shimatani, Hiroyuki; Hayashi, Hida; Chao, Hsu-Wen; Nakagawa, Yuuki; Takahashi, Yukari; Hotta, Yunhong; Yasunaga, Jun-ichirou; Matsuoka, Masao; Hastings, Michael H.; Kiyonari, Hiroshi; Okamura, Hitoshi

    2016-01-01

    G-protein-coupled receptors (GPCRs) participate in a broad range of physiological functions. A priority for fundamental and clinical research, therefore, is to decipher the function of over 140 remaining orphan GPCRs. The suprachiasmatic nucleus (SCN), the brain's circadian pacemaker, governs daily rhythms in behaviour and physiology. Here we launch the SCN orphan GPCR project to (i) search for murine orphan GPCRs with enriched expression in the SCN, (ii) generate mutant animals deficient in candidate GPCRs, and (iii) analyse the impact on circadian rhythms. We thereby identify Gpr176 as an SCN-enriched orphan GPCR that sets the pace of circadian behaviour. Gpr176 is expressed in a circadian manner by SCN neurons, and molecular characterization reveals that it represses cAMP signalling in an agonist-independent manner. Gpr176 acts independently of, and in parallel to, the Vipr2 GPCR, not through the canonical Gi, but via the unique G-protein subclass Gz. PMID:26882873

  10. Improved myocardial contractility with glucose-insulin-potassium infusion during pacing in coronary artery disease.

    PubMed

    McDaniel, H G; Rogers, W J; Russell, R O; Rackley, C E

    1985-04-01

    The metabolic and mechanical effects of a solution of glucose-insulin-potassium (G-I-K) were investigated in 18 patients who underwent diagnostic cardiac catheterization for coronary artery disease. All patients were paced at a rate of approximately 140 beats/min before and after infusion of G-I-K. Basal and paced left ventricular (LV) end-diastolic pressure, dP/dt, arterial substrate levels and osmolarity were measured in all 18 patients. In 13 patients cardiac index was also measured. In 5 patients arterial-coronary sinus measurements of oxygen, carbon dioxide, glucose, free fatty acids, lactate, alanine, glutamate, glutamine, ammonia and urea were made, in addition to coronary sinus blood flow. G-I-K increased the blood sugar level to approximately 200 mg/dl and raised the serum osmolarity 9 mosmol. Pacing alone raised the cardiac index 4% and pacing with G-I-K increased the cardiac index 6% (p less than 0.05). Pacing before G-I-K augmented dP/dt (21%) and pacing with G-I-K increased it (30%) (p less than 0.01). The metabolic changes noted included a shift in the respiratory quotient from 0.77 to 0.96 with G-I-K infusion (p less than 0.05). During G-I-K infusion the myocardial oxygen consumption at rest increased from 17.1 to 21.8 ml/min (23%, p less than 0.05). Myocardial oxygen consumption during pacing was similar before and after G-I-K infusion. Before G-I-K infusion nitrogen balance was slightly positive; after G-I-K infusion it was negative with regard to the nitrogen-containing compounds measured.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:3885708

  11. Using "U-Pace" Instruction to Improve the Academic Performance of Economically Disadvantaged Undergraduates

    ERIC Educational Resources Information Center

    Fleming, R.; Stoiber, L. C.; Pfeiffer, H. M.; Kienzler, S. E.; Fleming, R. R.; Pedrick, L. E.; Barth, D. J.; Reddy, D. .

    2016-01-01

    This study was undertaken to evaluate whether the student success associated with the "U-Pace" instructional approach, which integrates mastery-based learning with proactive instructor support in an online learning environment, would replicate for both economically disadvantaged students and students who are not economically…

  12. Centennial-scale climate change from decadally-paced explosive volcanism: a coupled sea ice-ocean mechanism

    NASA Astrophysics Data System (ADS)

    Zhong, Y.; Miller, G. H.; Otto-Bliesner, B. L.; Holland, M. M.; Bailey, D. A.; Schneider, D. P.; Geirsdottir, A.

    2011-12-01

    Northern Hemisphere summer cooling through the Holocene is largely driven by the steady decrease in summer insolation tied to the precession of the equinoxes. However, centennial-scale climate departures, such as the Little Ice Age, must be caused by other forcings, most likely explosive volcanism and changes in solar irradiance. Stratospheric volcanic aerosols have the stronger forcing, but their short residence time likely precludes a lasting climate impact from a single eruption. Decadally paced explosive volcanism may produce a greater climate impact because the long response time of ocean surface waters allows for a cumulative decrease in sea-surface temperatures that exceeds that of any single eruption. Here we use a global climate model to evaluate the potential long-term climate impacts from four decadally paced large tropical eruptions. Direct forcing results in a rapid expansion of Arctic Ocean sea ice that persists throughout the eruption period. The expanded sea ice increases the flux of sea ice exported to the northern North Atlantic long enough that it reduces the convective warming of surface waters in the subpolar North Atlantic. In two of our four simulations the cooler surface waters being advected into the Arctic Ocean reduced the rate of basal sea-ice melt in the Atlantic sector of the Arctic Ocean, allowing sea ice to remain in an expanded state for > 100 model years after volcanic aerosols were removed from the stratosphere. In these simulations the coupled sea ice-ocean mechanism maintains the strong positive feedbacks of an expanded Arctic Ocean sea ice cover, allowing the initial cooling related to the direct effect of volcanic aerosols to be perpetuated, potentially resulting in a centennial-scale or longer change of state in Arctic climate. The fact that the sea ice-ocean mechanism was not established in two of our four simulations suggests that a long-term sea ice response to volcanic forcing is sensitive to the stability of the seawater

  13. Protein-Pacing from Food or Supplementation Improves Physical Performance in Overweight Men and Women: The PRISE 2 Study

    PubMed Central

    Arciero, Paul J.; Edmonds, Rohan C.; Bunsawat, Kanokwan; Gentile, Christopher L.; Ketcham, Caitlin; Darin, Christopher; Renna, Mariale; Zheng, Qian; Zhang, Jun Zhu; Ormsbee, Michael J.

    2016-01-01

    We recently reported that protein-pacing (P; six meals/day @ 1.4 g/kg body weight (BW), three of which included whey protein (WP) supplementation) combined with a multi-mode fitness program consisting of resistance, interval sprint, stretching, and endurance exercise training (RISE) improves body composition in overweight individuals. The purpose of this study was to extend these findings and determine whether protein-pacing with only food protein (FP) is comparable to WP supplementation during RISE training on physical performance outcomes in overweight/obese individuals. Thirty weight-matched volunteers were prescribed RISE training and a P diet derived from either whey protein supplementation (WP, n = 15) or food protein sources (FP, n = 15) for 16 weeks. Twenty-one participants completed the intervention (WP, n = 9; FP, n = 12). Measures of body composition and physical performance were significantly improved in both groups (p < 0.05), with no effect of protein source. Likewise, markers of cardiometabolic disease risk (e.g., LDL (low-density lipoprotein) cholesterol, glucose, insulin, adiponectin, systolic blood pressure) were significantly improved (p < 0.05) to a similar extent in both groups. These results demonstrate that both whey protein and food protein sources combined with multimodal RISE training are equally effective at improving physical performance and cardiometabolic health in obese individuals. PMID:27187451

  14. Protein-Pacing from Food or Supplementation Improves Physical Performance in Overweight Men and Women: The PRISE 2 Study.

    PubMed

    Arciero, Paul J; Edmonds, Rohan C; Bunsawat, Kanokwan; Gentile, Christopher L; Ketcham, Caitlin; Darin, Christopher; Renna, Mariale; Zheng, Qian; Zhang, Jun Zhu; Ormsbee, Michael J

    2016-01-01

    We recently reported that protein-pacing (P; six meals/day @ 1.4 g/kg body weight (BW), three of which included whey protein (WP) supplementation) combined with a multi-mode fitness program consisting of resistance, interval sprint, stretching, and endurance exercise training (RISE) improves body composition in overweight individuals. The purpose of this study was to extend these findings and determine whether protein-pacing with only food protein (FP) is comparable to WP supplementation during RISE training on physical performance outcomes in overweight/obese individuals. Thirty weight-matched volunteers were prescribed RISE training and a P diet derived from either whey protein supplementation (WP, n = 15) or food protein sources (FP, n = 15) for 16 weeks. Twenty-one participants completed the intervention (WP, n = 9; FP, n = 12). Measures of body composition and physical performance were significantly improved in both groups (p < 0.05), with no effect of protein source. Likewise, markers of cardiometabolic disease risk (e.g., LDL (low-density lipoprotein) cholesterol, glucose, insulin, adiponectin, systolic blood pressure) were significantly improved (p < 0.05) to a similar extent in both groups. These results demonstrate that both whey protein and food protein sources combined with multimodal RISE training are equally effective at improving physical performance and cardiometabolic health in obese individuals. PMID:27187451

  15. Pace Yourself.

    ERIC Educational Resources Information Center

    Small, Ann R.

    1979-01-01

    Suggests techniques and behaviors teachers can use to optimize the flow and pacing of their music lessons. Included are techniques for timing the lesson, keeping students involved, and minimizing interruptions and transitions. (SJL)

  16. Keeping Pace

    ERIC Educational Resources Information Center

    Henderson, Nancy

    2008-01-01

    This article describes the struggles of two tough moms who team up to start their own company. Fed up with a lack of stylish, properly-fitting shoes for their children with cerebral palsy, they established "Keeping Pace" which currently offers a selection of stylish girls' and boys' athletic sneakers and casual dress shoes for boys, all sold…

  17. Improving Responsiveness to Intervention for English-Language Learners: A Comparison of Instructional Pace on Letter Naming Rates

    ERIC Educational Resources Information Center

    Gilbertson, Donna; Bluck, John

    2006-01-01

    An alternating treatments design was used to compare the effects of a 1-s and a 5-s paced intervention on rates of letter naming by English Language Learners (ELL). Participants were four kindergarten students performing below the average letter naming level and learning rate than other ELL classmates. The fast paced intervention consisted of a…

  18. Improvement of magnetic interface coupling through a magnetic coupling gel

    SciTech Connect

    Chen, Z.J.; Negley, M.; Jiles, D.C. |; Sablik, M.J.

    1995-11-01

    Surface measurement of magnetic properties is potentially a very advantageous technique for nondestructive evaluation. The effect of a magnetic coupling gel on surface magnetic measurement, is reported in this paper. Test results under three interface conditions are presented and compared. It was found that the magnetic gel reduces the variability of the measurement by improving the magnetic interface coupling between the sensor and test specimen. A simple model of a magnetic circuit is analyzed to show the coupling function of magnetic gel. From these results, it is deduced that the magnetic coupling gel plays an important part in improving reliability of the magnetic measurements. The specimens used in this investigation were three pieces of P22 Cr-Mo steel.

  19. PACE Status Update

    SciTech Connect

    M., Zimring,; Hoffman, I.; Fuller, M.

    2010-08-11

    The Federal Housing Finance Agency (FHFA) regulates Fannie Mae, Freddie Mac, and the 12 Federal Home Loan Banks (the government-sponsored enterprises - GSEs). On July 6, 2010, FHFA and the Office of the Comptroller of the Currency (OCC) concluded that Property Assessed Clean Energy (PACE) programs 'present significant safety and soundness concerns' to the housing finance industry. This statement came after a year of discussions with state and federal agencies in which PACE, a novel mechanism for financing energy efficiency and renewable energy improvements, has gone from receiving support from the White House, canonization as one of Scientific American's 'World Changing Ideas' and legislative adoption in 24 states to questionable relevance, at least in the residential sector. Whether PACE resumes its expansion as an innovative tool for financing energy efficiency and clean generation depends on outcomes in each of the three branches of government - discussions on a PACE pilot phase among federal agencies, litigation in federal court, and legislation in Congress - all highly uncertain. This policy brief addresses the practical impacts of these possible outcomes on existing and emerging PACE programs across the United States and potential paths forward.

  20. Project for Program Improvement through the Utilization of Self-Paced Individualized Instruction Concepts Industrial Equipment Technology. Final Report.

    ERIC Educational Resources Information Center

    Crowley's Ridge Vocational Technical School, Forrest City, AR.

    The general objectives of an Arkansas technical school's self-paced individualized instruction program were designing, field testing, and disseminating an instructional management system with support materials that identify and justify the need for a program of instruction. Eight specific objectives have been developed to facilitate students'…

  1. Polished Downhole Transducer Having Improved Signal Coupling

    DOEpatents

    Hall, David R.; Fox, Joe

    2006-03-28

    Apparatus and methods to improve signal coupling in downhole inductive transmission elements to reduce the dispersion of magnetic energy at the tool joints and to provide consistent impedance and contact between transmission elements located along the drill string. A transmission element for transmitting information between downhole tools is disclosed in one embodiment of the invention as including an annular core constructed of a magnetically conductive material. The annular core forms an open channel around its circumference and is configured to form a closed channel by mating with a corresponding annular core along an annular mating surface. The mating surface is polished to provide improved magnetic coupling with the corresponding annular core. An annular conductor is disposed within the open channel.

  2. Coupled improvement between thermoelectric and piezoelectric materials

    NASA Astrophysics Data System (ADS)

    Montgomery, David; Hewitt, Corey; Dun, Chaochao; Carroll, David

    A novel coupling effect in a thermoelectric and piezoelectric meta-structure is discussed. Thermo-piezoelectric generators (TPEGs) exhibit a synergistic effect that amplifies output voltage, and has been observed to increase piezoelectric voltages over 500% of initial values a time dependent thermoelectric/pyroelectric effect. The resulting improvement in voltage has been observed in carbon nanotubes as well as inorganics such as two-dimensional Bismuth Selenide platelets and Telluride nanorods thin-film thermoelectrics. TPEGs are built by integrating insulating layers of polyvinylidene fluoride (PVDF) piezoelectric films between flexible thin film p-type and n-type thermoelectrics. The physical phenomena arising in the interaction between thermoelectric and piezoelectrics is discussed and a model is presented to quantify the expected coupling voltage as a function of stress, thermal gradient, and different thermoelectric materials. TPEG are ideal to capture waste heat and vibrational energy while creating larger voltages and minimizing space when compared with similar thermoelectric or piezoelectric generators.

  3. Toward Improved Support for Loosely Coupled Large Scale Simulation Workflows

    SciTech Connect

    Boehm, Swen; Elwasif, Wael R; Naughton, III, Thomas J; Vallee, Geoffroy R

    2014-01-01

    High-performance computing (HPC) workloads are increasingly leveraging loosely coupled large scale simula- tions. Unfortunately, most large-scale HPC platforms, including Cray/ALPS environments, are designed for the execution of long-running jobs based on coarse-grained launch capabilities (e.g., one MPI rank per core on all allocated compute nodes). This assumption limits capability-class workload campaigns that require large numbers of discrete or loosely coupled simulations, and where time-to-solution is an untenable pacing issue. This paper describes the challenges related to the support of fine-grained launch capabilities that are necessary for the execution of loosely coupled large scale simulations on Cray/ALPS platforms. More precisely, we present the details of an enhanced runtime system to support this use case, and report on initial results from early testing on systems at Oak Ridge National Laboratory.

  4. Permanent cardiac pacing in pediatric patients.

    PubMed

    Lotfy, Wael; Hegazy, Ranya; AbdElAziz, Osama; Sobhy, Rodina; Hasanein, Hossam; Shaltout, Fawzan

    2013-02-01

    Pediatric pacemaker (PM) implants comprise less than 1 % of all PM implants. This study aimed to investigate permanent cardiac pacing among the pediatric population, identifying different indications and complications of pediatric cardiac pacing, especially focusing on the effect of the pacing sites, the PM lead type, and the indications for pacing. The current work is a cross-sectional study of 103 procedures for permanent PM insertion in pediatric patients between January 2001 and December 2010. The patients were followed up 1, 3, and 6 months after implantation, then every 6 months or as needed. Evaluation included routine clinical examination, electrocardiography, chest X-ray, echocardiography, and a full analysis of the pacing system measurements. The ages of the patients ranged from 0.09 to 12 years (median, 2.3 years). The most common indication for pacing was postoperative complete heart bock, noted in 54 patients (52.4 %). Transvenous endocardial PM insertion was performed in 92 procedures (89.3 %), whereas transthoracic epicardial insertion was performed in 11 procedures (10.7 %). The most common site of pacing was the right ventricular apex (n = 64, 62 %), followed by the right ventricular outflow tract (n = 25, 24.3 %). Transthoracic epicardial PM insertion was associated with a significantly higher percentage and greater severity of complications. In this study, 65 % of the patients with left ventricle (LV) dilation before pacing showed a significant improvement in LV dimensions and function after pacing. This was noted only in those with endocardially inserted PM leads in both the congenital and the postoperative groups regardless of the pacing site. Endocardial PM insertion in children is a safe procedure with fewer complications and a lower ventricular threshold than the epicardial route. Permanent single-chamber right ventricle pacing is safe and can lead to significant improvement in LV function and dimensions. However, long-term follow

  5. Reversal of Pacing-Induced Cardiomyopathy by Normal QRS Axis Pacing

    PubMed Central

    Yang, Ji Hyun; Kim, Ju Youn; Kim, Sung-Hwan

    2016-01-01

    Right ventricular apical pacing has been a commonly used method for placement of permanent pacemaker, but it is known to be associated with ventricular dyssynchrony and may lead to heart failure. Septal pacing could be an alternative method to improve this complication but the results have been conflicting; hence, other strategies are needed. This case is about a patient with pacing-induced cardiomyopathy who showed much improvement after repositioning the leads to a site different from that of normally paced QRS axis. PMID:27275181

  6. Mining apparatus having an improved coupling assembly

    SciTech Connect

    Ingle, J.E.

    1981-09-08

    A mining apparatus is disclosed for excavating material from an earth formation having a miner which is removably connectable to a carrier by a coupling assembly. The mining apparatus includes other carriers which are interconnected by the coupling assembly of the present invention. The coupling assembly includes a male connector and a female connector, the male connector being disposable in a portion of the female connector in an insert position and the male connector being movable from the insert position to a connected position for interconnecting the male and the female connectors.

  7. Effect of Adaptive Paced Cardiolocomotor Synchronization During Running: A Preliminary Study

    PubMed Central

    Phillips, Bill; Jin, Yi

    2013-01-01

    Cardiolocomotor synchronization (CLS) has been well established for individuals engaged in rhythmic activity, such as walking, running, or cycling. When frequency of the activity is at or near the heart rate, entrainment occurs. CLS has been shown in many cases to improve the efficiency of locomotor activity, improving stroke volume, reducing blood pressure variability, and lowering the oxygen uptake (VO2). Instead of a 1:1 frequency ratio of activity to heart rate, an investigation was performed to determine if different harmonic coupling at other simple integer ratios (e.g. 1:2, 2:3, 3:2) could achieve any performance benefits. CLS was ensured by pacing the stride rate according to the measured heartbeat (i.e., adaptive paced CLS, or forced CLS). An algorithm was designed that determined the simplest ratio (lowest denominator) that, when multiplied by the heart rate will fall within an individualized, predetermined comfortable pacing range for the user. The algorithm was implemented on an iPhone 4, which generated a ‘tick-tock’ sound through the iPhone’s headphones. A sham-controlled crossover study was performed with 15 volunteers of various fitness levels. Subjects ran a 3 mile (4.83 km) simulated training run at their normal pace on two consecutive days (randomized one adaptive pacing, one sham). Adaptive pacing resulted in faster runs run times, with subjects running an average of 26:03 ± 3:23 for adaptive pacing and 26:38 ± 3:31 for sham (F = 5.46, p < 0.05). The increase in heart rate from the start of the race as estimated by an exponential time constant was significantly longer during adaptive pacing, τ = 0.99 ± 0.30, compared to sham, τ = 1.53 ± 0.34 (t = -6.62, p < 0.01). Eighty-seven percent of runners found it easy to adjust their stride length to match the pacing signal with seventy-nine percent reporting that pacing helped their performance. These results suggest that adaptive paced CLS may have a beneficial effect on running performance

  8. Self-Paced Fortran.

    ERIC Educational Resources Information Center

    Burnett, James

    1979-01-01

    This paper describes the instructional format of the lecture and the self-paced methods of teaching FORTRAN at Michigan State University and compares end-of-term grades of students taking a second computer science course based on whether they took the first course in the self-paced or the traditional lecture format. (Author/BB)

  9. Coupling device with improved thermal interface

    NASA Technical Reports Server (NTRS)

    Milam, Malcolm Bruce (Inventor)

    1992-01-01

    The primary object of the present invention is to provide a simple, reliable, and lightweight coupling that will also have an efficient thermal interface. A further object of the invention is to provide a coupling that is capable of blind mating with little or no insertion forces. Another object of the invention is to provide a coupling that acts as a thermal regulator to maintain a constant temperature on one side of the coupling. Another object of the invention is to increase the available surface area of a coupling thus providing a larger area for the conduction of heat across the thermal interface. Another object of the invention is to provide a fluidic coupling that has no fluid passing across the interface, thus reducing the likelihood of leaks and contamination. The foregoing objects are achieved by utilizing, as in the prior art, a hot area (at an elevated temperature as compared to a cold area) with a need to remove excess heat from the hot area to a cold area. In this device, the thermal interface will occur not on a planar horizontal surface, but along a non-planar vertical surface, which will reduce the reaction forces and increase the thermal conductivity of the device. One non-planar surface is a surface on a cold pin extending from the cold area and the other non-planar surface is a surface on a hot pin extending from the hot area. The cold pin is fixed and does not move while the hot pin is a flexible member and its movement towards the cold pin will bring the two non-planar surfaces together forming the thermal interface. The actuating member for the device is a shape-memory actuation wire which is attached through an aperture to the hot pin and through another aperture to an actuation wire retainer. By properly programming the actuation wire, heat from the hot area will cause the actuation wire to bend the hot wire. Heat from the hot area will cause the actuation wire to bend the hot pin towards the cold pin forming the coupling and the desired

  10. Development and evaluation of the feasibility and effects on staff, patients, and families of a new tool, the Psychosocial Assessment and Communication Evaluation (PACE), to improve communication and palliative care in intensive care and during clinical uncertainty

    PubMed Central

    2013-01-01

    Background There are widespread concerns about communication and support for patients and families, especially when they face clinical uncertainty, a situation most marked in intensive care units (ICUs). Therefore, we aimed to develop and evaluate an interventional tool to improve communication and palliative care, using the ICU as an example of where this is difficult. Methods Our design was a phase I-II study following the Medical Research Council Guidance for the Development and Evaluation of Complex Interventions and the (Methods of Researching End-of-life Care (MORECare) statement. In two ICUs, with over 1900 admissions annually, phase I modeled a new intervention comprising implementation training and an assessment tool. We conducted a literature review, qualitative interviews, and focus groups with 40 staff and 13 family members. This resulted in the new tool, the Psychosocial Assessment and Communication Evaluation (PACE). Phase II evaluated the feasibility and effects of PACE, using observation, record audit, and surveys of staff and family members. Qualitative data were analyzed using the framework approach. The statistical tests used on quantitative data were t-tests (for normally distributed characteristics), the χ2 or Fisher’s exact test (for non-normally distributed characteristics) and the Mann–Whitney U-test (for experience assessments) to compare the characteristics and experience for cases with and without PACE recorded. Results PACE provides individualized assessments of all patients entering the ICU. It is completed within 24 to 48 hours of admission, and covers five aspects (key relationships, social details and needs, patient preferences, communication and information status, and other concerns), followed by recording of an ongoing communication evaluation. Implementation is supported by a training program with specialist palliative care. A post-implementation survey of 95 ICU staff found that 89% rated PACE assessment as very or

  11. Improving data transfer for model coupling

    NASA Astrophysics Data System (ADS)

    Zhang, C.; Liu, L.; Yang, G.; Li, R.; Wang, B.

    2015-10-01

    Data transfer, which means transferring data fields between two component models or rearranging data fields among processes of the same component model, is a fundamental operation of a coupler. Most of state-of-the-art coupler versions currently use an implementation based on the point-to-point (P2P) communication of the Message Passing Interface (MPI) (call such an implementation "P2P implementation" for short). In this paper, we reveal the drawbacks of the P2P implementation, including low communication bandwidth due to small message size, variable and big number of MPI messages, and jams during communication. To overcome these drawbacks, we propose a butterfly implementation for data transfer. Although the butterfly implementation can outperform the P2P implementation in many cases, it degrades the performance in some cases because the total message size transferred by the butterfly implementation is larger than that by the P2P implementation. To make the data transfer completely improved, we design and implement an adaptive data transfer library that combines the advantages of both butterfly implementation and P2P implementation. Performance evaluation shows that the adaptive data transfer library significantly improves the performance of data transfer in most cases and does not decrease the performance in any cases. Now the adaptive data transfer library is open to the public and has been imported into a coupler version C-Coupler1 for performance improvement of data transfer. We believe that it can also improve other coupler versions.

  12. Physiological cardiac pacing: Current status.

    PubMed

    Das, Asit; Kahali, Dhiman

    2016-01-01

    Adverse hemodynamics of right ventricular (RV) pacing is a well-known fact. It was believed to be the result of atrio-ventricular (AV) dyssynchrony and sequential pacing of the atrium and ventricle may solve these problems. However, despite maintenance of AV synchrony, the dual chamber pacemakers in different trials have failed to show its superiority over single chamber RV apical pacing in terms of death, progression of heart failure, and atrial fibrillation (AF). As a consequence, investigators searched for alternate pacing sites with a more physiological activation pattern and better hemodynamics. Direct His bundle pacing and Para-Hisian pacing are the most physiological ventricular pacing sites. But, this is technically difficult. Ventricular septal pacing compared to apical pacing results in a shorter electrical activation delay and consequently less mechanical dyssynchrony. But, the study results are heterogeneous. Selective site atria pacing (atrial septal) is useful for patients with atrial conduction disorders in prevention of AF. PMID:27543481

  13. Improving entanglement of two atoms in strong coupling regime

    NASA Astrophysics Data System (ADS)

    Liu, Hui; Yang, Qing; Yang, Ming; Cao, Zhuoliang

    2016-03-01

    We consider a model of two identical atoms coupled to a single-mode cavity. When in atom-field strong coupling regime, the entanglement of the two atoms with spontaneous emission should be investigated beyond rotating-wave approximation (RWA). In order to improve the entanglement of the two atoms, some typical feedback based on quantum-jump are attempted to impose on the atoms. The result of numerical simulations shows that an appropriate feedback control can improve the entanglement.

  14. Coupled Facility/Payload Vibration Modeling Improvements

    NASA Technical Reports Server (NTRS)

    Carnahan, Timothy M.; Kaiser, Michael

    2015-01-01

    A major phase of aerospace hardware verification is vibration testing. The standard approach for such testing is to use a shaker to induce loads into the payload. In preparation for vibration testing at NASA/GSFC there is an analysis to assess the responses of the payload. A new method of modeling the test is presented that takes into account dynamic interactions between the facility and the payload. This dynamic interaction has affected testing in the past, but been ignored or adjusted for during testing. By modeling the combination of the facility and test article (payload) it is possible to improve the prediction of hardware responses. Many aerospace test facilities work in similar way to those at NASA Goddard Space Flight Center. Lessons learned here should be applicable to other test facilities with similar setups.

  15. Coupled Facility-Payload Vibration Modeling Improvements

    NASA Technical Reports Server (NTRS)

    Carnahan, Timothy M.; Kaiser, Michael A.

    2015-01-01

    A major phase of aerospace hardware verification is vibration testing. The standard approach for such testing is to use a shaker to induce loads into the payload. In preparation for vibration testing at National Aeronautics and Space Administration/Goddard Space Flight Center an analysis is performed to assess the responses of the payload. A new method of modeling the test is presented that takes into account dynamic interactions between the facility and the payload. This dynamic interaction has affected testing in the past, but been ignored or adjusted for during testing. By modeling the combined dynamics of the facility and test article (payload) it is possible to improve the prediction of hardware responses. Many aerospace test facilities work in similar way to those at NASA/Goddard Space Flight Center. Lessons learned here should be applicable to other test facilities with similar setups.

  16. Promoting continence in nursing homes in four European countries: the use of PACES as a mechanism for improving the uptake of evidence-based recommendations

    PubMed Central

    Harvey, Gill; Kitson, Alison; Munn, Zachary

    2012-01-01

    Background Multi-faceted approaches are generally recognised as the most effective way to support the implementation of evidence into practice. Audit and feedback often constitute one element of a multi-faceted implementation package, alongside other strategies, such as interactive education and facilitated support mechanisms. This paper describes a multi-faceted implementation strategy that used the Joanna Briggs Institute Practical Application of Clinical Evidence System (PACES) as an online audit tool to support facilitators working to introduce evidence-based continence recommendations in nursing homes in four different European countries. Aims/objectives The paper describes the experience of using PACES with an international group of nursing home facilitators. In particular, the objectives of the paper are: to describe the process of introducing PACES to internal facilitators in eight nursing homes; to discuss the progress made during a 12-month period of collecting and analysing audit data using PACES; to summarise the collective experience of using PACES, including reflections on its strengths and limitations. Methods Descriptive data were collected during the 12-month period of working with PACES in the eight nursing home sites. These data included digital and written notes taken at an initial 3-day introductory programme, at monthly teleconferences held between the external and internal facilitators and at a final 2-day meeting. Qualitative analysis of the data was undertaken on an ongoing basis throughout the implementation period, which enabled formative evaluation of PACES. A final summative evaluation of the experience of using PACES was undertaken as part of the closing project meeting in June 2011. Results The nursing home facilitators took longer than anticipated to introduce PACES and it was only after 9–10 months that they became confident and comfortable using the system. This was due to a combination of factors, including a lack of audit

  17. Transferring PACE Assessments Upon Home Sale

    SciTech Connect

    National Renewable Energy Laboratory; Coughlin, Jason; Fuller, Merrian; Zimring, Mark

    2010-04-12

    A significant barrier to investing in renewable energy and comprehensive energy efficiency improvements to homes across the country is the initial capital cost. Property Assessed Clean Energy (PACE) financing is one of several new financial models broadening access to clean energy by addressing this upfront cost issue. Recently, the White House cited PACE programs as an important element of its 'Recovery through Retrofit' plan. The residential PACE model involves the creation of a special clean energy financing district that homeowners elect to opt into. Once opted in, the local government (usually at the city or county level) finances the upfront investment of the renewable energy installation and/or energy efficiency improvements. A special lien is attached to the property and the assessment is paid back as a line item on the property tax bill. As of April 2010, 17 states have passed legislation to allow their local governments to create PACE programs, two already have the authority to set up PACE programs, and over 10 additional states are actively developing enabling legislation. This policy brief analyzes one of the advantages of PACE, which is the transferability of the special assessment from one homeowner to the next when the home is sold. This analysis focuses on the potential for the outstanding lien to impact the sales negotiation process, rather than the legal nature of the lien transfer itself. The goal of this paper is to consider what implications a PACE lien may have on the home sales negotiation process so that it can be addressed upfront rather than risk a future backlash to PACE programs. If PACE programs do expand at a rapid rate, the chances are high that there will be other cases where prospective buyers uses PACE liens to negotiate lower home prices or require repayment of the lien as a condition of sale. As a result, PACE programs should highlight this issue as a potential risk factor for the sake of full disclosure. A good example of this

  18. Self-Paced Studies.

    ERIC Educational Resources Information Center

    Faust, Norma Jean

    1995-01-01

    Discusses the use of self-paced units. Development suggestions include determining the form of the units, including goals, responsibilities, and definitions of terms; keeping them short; including a variety of activities; and requiring that all lessons be completed at school. Contains sample units on climatology and meteorology, the sun, and…

  19. Improvement of left ventricular filling by ivabradine during chronic hypertension: involvement of contraction-relaxation coupling.

    PubMed

    Melka, Jonathan; Rienzo, Mario; Bizé, Alain; Jozwiak, Mathieu; Sambin, Lucien; Hittinger, Luc; Su, Jin Bo; Berdeaux, Alain; Ghaleh, Bijan

    2016-05-01

    Chronic hypertension is associated with left ventricular (LV) hypertrophy and LV diastolic dysfunction with impaired isovolumic relaxation and abnormal LV filling. Increased heart rate (HR) worsens these alterations. We investigated whether the I f channel blocker ivabradine exerts beneficial effects on LV filling dynamic. In this setting, we also evaluated the relationship between LV filling and isovolumic contraction as a consequence of contraction-relaxation coupling. Therefore, hypertension was induced by a continuous infusion of angiotensin II during 28 days in 10 chronically instrumented pigs. LV function was investigated after stopping angiotensin II infusion to offset the changes in loading conditions. In the normal heart, LV relaxation filling, LV early filling, LV peak early filling rate were positively correlated to HR. In contrast, these parameters were significantly reduced at day 28 vs. day 0 (18, 42, and 26 %, respectively) despite the increase in HR (108 ± 6 beats/min vs. 73 ± 2 beats/min, respectively). These abnormalities were corrected by acute administration of ivabradine (1 mg/kg, iv). Ivabradine still exerted these effects when HR was controlled at 150 beats/min by atrial pacing. Interestingly, LV relaxation filling, LV early filling and LV peak early filling were strongly correlated with both isovolumic contraction and relaxation. In conclusion, ivabradine improves LV filling during chronic hypertension. The mechanism involves LV contraction-relaxation coupling through normalization of isovolumic contraction and relaxation as well as HR-independent mechanisms. PMID:27040115

  20. Cardiac pacing and aviation.

    PubMed

    Toff, W D; Edhag, O K; Camm, A J

    1992-12-01

    Certain applicants with stable disturbances of rhythm or conduction requiring cardiac pacing, in whom no other disqualifying condition is present, may be considered fit for medical certification restricted to multi-crew operations. The reliability of modern pacing systems appears adequate to permit restricted certification even in pacemaker dependent subjects except for certain models of pacemakers and leads known to be at increased risk of failure. These are to be avoided. There is little evidence to suggest that newer devices are any more reliable than their predecessors. Single and dual chamber systems appear to have similar reliability up to 4 years, after which time significant attrition of dual chamber devices occurs, principally due to battery depletion. All devices require increased scrutiny as they approach their end of life as predicted from longevity data and pacing characteristics. Unipolar and bipolar leads are of similar reliability, apart from a number of specific bipolar polyurethane leads which have been identified. Atrial leads, particularly those without active fixation, are less secure than ventricular leads and applicants who are dependent on atrial sensing or pacing should be denied certification. Bipolar leads are to be preferred due to the lower risk of myopotential and exogenous EMI. Sensor-driven adaptive-rate pacing systems using active sensors may have reduced longevity and require close scrutiny. Activity-sensing devices using piezoelectric crystal sensors may be subject to significant rate rises in rotary wing aircraft. The impracticality of restricted certification in helicopters will, in any event, preclude certification. Such devices would best be avoided in hovercraft (air cushioned vehicle) pilots. Only minor rate rises are likely in fixed-wing aircraft which are unlikely to be of significance. Anti-tachycardia devices and implanted defibrillators are inconsistent with any form of certification to fly. PMID:1493823

  1. Optimized multisite ventricular pacing in postoperative single-ventricle patients.

    PubMed

    Havalad, Vinod; Cabreriza, Santos E; Cheung, Eva W; Aponte-Patel, Linda; Wang, Alice; Cheng, Bin; Wang, Daniel Y; Silver, Eric; Bacha, Emile A; Spotnitz, Henry M

    2014-10-01

    Ventricular dyssynchrony is associated with morbidity and mortality after palliation of a single ventricle. The authors hypothesized that resynchronization with optimized temporary multisite pacing postoperatively would be safe, feasible, and effective. Pacing was assessed in the intensive care unit within the first 24 h after surgery. Two unipolar atrial pacing leads and four bipolar ventricular pacing leads were placed at standardized sites intraoperatively. Pacing was optimized to maximize mean arterial pressure. The protocol tested 11 combinations of the 4 different ventricular lead sites, 6 atrioventricular delays (50-150 ms), and 14 intraventricular delays. Optimal pacing settings were thus determined and ultimately compared in four configurations: bipolar, unipolar, single-site atrioventricular pacing, and intrinsic rhythm. Each patient was his or her own control, and all pacing comparisons were implemented in random sequence. Single-ventricle palliation was performed for 17 children ages 0-21 years. Pacing increased mean arterial pressure (MAP) versus intrinsic rhythm, with the following configurations: bipolar multisite pacing increased MAP by 2.2 % (67.7 ± 2.4 to 69.2 ± 2.4 mmHg; p = 0.013) and unipolar multisite pacing increased MAP by 2.8 % (67.7 ± 2.4 to 69.6 ± 2.7 mmHg; p = 0.002). Atrioventricular single-site pacing increased MAP by 2.1 % (67.7 ± 2.4 to 69.1 ± 2.5 mmHg: p = 0.02, insignificant difference under Bonferroni correction). The echocardiographic fractional area change in nine patients increased significantly only with unipolar pacing (32 ± 3.1 to 36 ± 4.2 %; p = 0.02). No study-related adverse events occurred. Multisite pacing optimization is safe and feasible in the early postoperative period after single-ventricle palliation, with improvements in mean arterial pressure and fractional area shortening. Further study to evaluate clinical benefits is required. PMID:24827078

  2. TCP Pacing Developed

    NASA Technical Reports Server (NTRS)

    Ivancic, William D.

    2002-01-01

    Transmission control protocol (TCP) was conceived and designed to run over a variety of communication links, including wireless and high-bandwidth links. However, with recent technological advances in satellite and fiber-optic networks, researchers are reevaluating the flexibility of TCP. The TCP pacing and packet pair probing implementation may help overcome two of the major obstacles identified for efficient bandwidth utilization over communication links with large delay-bandwidth products.

  3. Coupling procedure modification improves sealing integrity of API connections

    SciTech Connect

    Chelette, K.D.; Bollfrass, C.A.

    1983-04-04

    This paper presents and recommends a pipe coupling procedure which provides several new options for improving the pressure sealing integrity of APILTC and Buttress casing connections. The combination of close tolerance control of taper and multiple tapers along the coupling thread length will ensure proper thread engagement and interference to produce the necessary surface contact pressures to seal and rate the coupling at the API pipe body internal yield pressure without the increased coupling OD values that will otherwise be required. The taper control of the first few threads of the coupling together with the steeper taper in the region of the pipe end, power-tight position ensures that sealing will occur at the extremes of the engaged thread length. This will exclude well bore pressures from the threaded region, thus reducing a tendency for jumpout at tensile loads less than the rated tensile failure load. The close taper tolerances and steeper taper section of the coupling will introduce a new capability to control the location of the final assembly position of the pipe in the coupling, providing for positive positional control of assembly without turn measure equipment.

  4. Controlled transient respiratory arrest along with rapid right ventricular pacing for improving balloon stability during balloon valvuloplasty in pediatric patients with congenital aortic stenosis--a retrospective case series analysis.

    PubMed

    Gupta, Sampa Dutta; Das, Soumi; Ghose, Tapas; Sarkar, Achyut; Goswami, Anupam; Kundu, Sudeshna

    2010-01-01

    Rapid right ventricular pacing is safe, effective, and established method to provide balloon stability during balloon aortic valvuloplasty (BAV). Controlled transient respiratory arrest at this point of time may further reduce left ventricular stroke volume, providing an additional benefit to maintain balloon stability. Two groups were studied. Among the 10 patients, five had rapid pacing alone (Group A), while the other five were provided with cessation of positive pressure breathing as well (Group B). The outcomes of BAV in the two groups of patients were studied. One patient in Group A had failed balloon dilatation even after the fourth attempt, while in Group B there were no failures. The peak systolic gradient reduction was higher in Group B (70.05% in comparison to 52.16% of group A). In Group A, five subjects developed aortic regurgitation (grade 2 in four and grade 3 in one, while no grade 3 aortic regurgitation developed in any patient in Group B). Controlled transient respiratory arrest along with rapid ventricular pacing may be effective in maintaining balloon stability and improve the outcome of BAV. PMID:20826965

  5. Enact legislation supporting residential property assessed clean energy financing (PACE)

    SciTech Connect

    Saha, Devashree

    2012-11-15

    Congress should enact legislation that supports residential property assessed clean energy (PACE) programs in the nation’s states and metropolitan areas. Such legislation should require the Federal Housing Finance Agency (FHFA) to allow Fannie Mae and Freddie Mac to purchase residential mortgages with PACE assessments while at the same time providing responsible underwriting standards and a set of benchmarks for residential PACE assessments in order to minimize financial risks to mortgage holders. Congressional support of residential PACE financing will improve energy efficiency, encourage job creation, and foster economic growth in the nation’s state and metropolitan areas.

  6. [The best of cardiac pacing in 1999].

    PubMed

    Deharo, J C

    2000-01-01

    Since the first clinical application to man forty years ago, for the treatment of bradycardia, cardiac pacing has been the object of continuous technological innovation in parallel with those in electronics and computerisation. However, independently of these expected advances, there has been a surprising widening of the field of application of pacing into those of haemodynamics and rhythmology. The recent publication of the long-term results of the Pacing in Cardiomyopathy (PIC) study confirmed the sustained decrease of intraventricular pressure gradient, of NYHA functional stage and improved quality of life of patients with hypertrophic obstructive cardiomyopathy paced in the DDD mode. The investigators also underlined the placebo effect of the pacemaker. The decrease in risk of sudden death and the reduction in ventricular remodelling have not been demonstrated yet. More recently, biventricular pacing has been proposed for the treatment of dilated cardiomyopathy and a French study showed a long-term improvement in NYHA stage and effort capacity. Several prospective randomised trials are under way to validate this indication. Acute haemodynamic evaluations have confirmed the efficacy of biventricular stimulation but also underline the value of left ventricular pacing alone. The effects on mortality, the selection of patients and the optimal configuration of pacing remain to be defined. In the field of prevention of atrial arrhythmias, the results of the multicenter SYNBIAPACE study, investigating biatrial pacing in patients with interatrial conduction defects, only showed a tendency to an increase in the delay before recurrence of atrial fibrillation. The value of the memory functions of pacemakers and the algorithms of prevention of atrial arrhythmias are still under investigation. Haemodynamic transducers have been introduced in some recent pacemakers to assess myocardial contractility and have applications in the evaluation of different pacing modes and in the

  7. Improvements in antenna coupling path algorithms for aircraft EMC analysis

    NASA Astrophysics Data System (ADS)

    Bogusz, Michael; Kibina, Stanley J.

    The algorithms to calculate and display the path of maximum electromagnetic interference coupling along the perfectly conducting surface of a frustrum cone model of an aircraft nose are developed and revised for the Aircraft Inter-Antenna Propagation with Graphics (AAPG) electromagnetic compatibility analysis code. Analysis of the coupling problem geometry on the frustrum cone model and representative numerical test cases reveal how the revised algorithms are more accurate than their predecessors. These improvements in accuracy and their impact on realistic aircraft electromagnetic compatibility problems are outlined.

  8. Noninvasive external cardiac pacing for thallium-201 scintigraphy

    SciTech Connect

    Feldman, M.D.; Warren, S.E.; Gervino, E.V.; Aroesty, J.M.; Royal, H.D.; Parker, J.A.; Silverman, K.J.; Kolodny, G.M.; Zoll, P.M.; McKay, R.G.

    1988-01-01

    Improvements in noninvasive external cardiac pacing have led to a technique with reliable electrical capture and tolerable patient discomfort. To assess the use of this modality of pacing in combination with thallium scintigraphy as a noninvasive pacing stress test, we applied simultaneous noninvasive cardiac pacing, hemodynamic monitoring, and thallium-201 scintigraphy in 14 patients undergoing cardiac catheterization for chest pain syndromes. Two patients had normal coronary arteries, while the remaining 12 had significant coronary artery disease. Thallium scintigraphic responses to pacing were compared to routine exercise thallium stress testing in nine of these 14 patients. All patients were noninvasively paced to more than 85% of the age-predicted maximum heart rate. Twelve patients demonstrated reversible thallium defects, which corresponded in 11 cases to significant lesions seen on coronary angiography. Of nine patients who underwent both pacing and exercise thallium stress tests, comparable maximal rate-pressure products were achieved. Moreover, thallium imaging at peak pacing and during delayed views did not differ significantly from exercise thallium scintigraphy. A limiting factor associated with the technique was local patient discomfort, which occurred to some degree in all patients. We conclude that noninvasive external cardiac pacing together with thallium scintigraphy is capable of detecting significant coronary artery disease and may be comparable to routine exercise thallium stress testing. This new modality of stress testing could be useful in patients unable to undergo the exercise required for standard exercise tolerance testing, particularly if improvements in the technology can be found to reduce further the local discomfort.

  9. Self-Paced Instruction: Hello, Education

    ERIC Educational Resources Information Center

    Leuba, Richard J.; Flammer, Gordon H.

    1975-01-01

    Answers criticisms of self-paced instruction (SPI) by citing advantages of SPI over lecture methods. Concludes that criticisms of SPI are useful since they indicate in which areas further research should be conducted to improve this method of instruction. (MLH)

  10. Visualizing Improved Spin Coupling in Large Magnetic Molecules

    NASA Astrophysics Data System (ADS)

    Donner, Judith; Broschinski, Jan-Philipp; Feldscher, Bastian; Glaser, Thorsten; Khajetoorians, Alexander Ako; Wegner, Daniel

    In an attempt to combine a high spin ground state and a large magnetic anisotropy in one molecule, triplesalen-based complexes are promising building blocks for a new generation of single molecule magnets (SMMs). The spin coupling in these molecules is based on the spin polarization effect, which requires a delocalized aromatic π-system in the central carbon ring of the complex. Unfortunately, chemical analysis indicates that this ring can change its configuration to [6]radialene, therefore causing a loss of aromaticity and weakening the magnetic coupling. We have employed a combination of scanning tunneling microscopy (STM) and spectroscopy (STS) to investigate single Cu3-triplesalen and Cu3-triplesalalen molecules, the latter being designed to show an enhanced intramolecular spin coupling. The large molecules were deposited in situ using the unconventional techniques pulse injection and rapid heating. A thorough structural and spectroscopic analysis allows us to discuss the electronic properties of the two complexes, with a special focus on the state of the central carbon ring. We find that even small changes in the ligand structure have a drastic influence on the intramolecular spin coupling, which opens the way for an improved rational design of future SMMs.

  11. Protein-Pacing and Multi-Component Exercise Training Improves Physical Performance Outcomes in Exercise-Trained Women: The PRISE 3 Study.

    PubMed

    Arciero, Paul J; Ives, Stephen J; Norton, Chelsea; Escudero, Daniela; Minicucci, Olivia; O'Brien, Gabe; Paul, Maia; Ormsbee, Michael J; Miller, Vincent; Sheridan, Caitlin; He, Feng

    2016-01-01

    The beneficial cardiometabolic and body composition effects of combined protein-pacing (P; 5-6 meals/day at 2.0 g/kg BW/day) and multi-mode exercise (resistance, interval, stretching, endurance; RISE) training (PRISE) in obese adults has previously been established. The current study examines PRISE on physical performance (endurance, strength and power) outcomes in healthy, physically active women. Thirty exercise-trained women (>4 days exercise/week) were randomized to either PRISE (n = 15) or a control (CON, 5-6 meals/day at 1.0 g/kg BW/day; n = 15) for 12 weeks. Muscular strength (1-RM bench press, 1-RM BP) endurance (sit-ups, SUs; push-ups, PUs), power (bench throws, BTs), blood pressure (BP), augmentation index, (AIx), and abdominal fat mass were assessed at Weeks 0 (pre) and 13 (post). At baseline, no differences existed between groups. Following the 12-week intervention, PRISE had greater gains (p < 0.05) in SUs, PUs (6 ± 7 vs. 10 ± 7, 40%; 8 ± 13 vs. 14 ± 12, 43% ∆reps, respectively), BTs (11 ± 35 vs. 44 ± 34, 75% ∆watts), AIx (1 ± 9 vs. -5 ± 11, 120%), and DBP (-5 ± 9 vs. -11 ± 11, 55% ∆mmHg). These findings suggest that combined protein-pacing (P; 5-6 meals/day at 2.0 g/kg BW/day) diet and multi-component exercise (RISE) training (PRISE) enhances muscular endurance, strength, power, and cardiovascular health in exercise-trained, active women. PMID:27258301

  12. Protein-Pacing and Multi-Component Exercise Training Improves Physical Performance Outcomes in Exercise-Trained Women: The PRISE 3 Study †

    PubMed Central

    Arciero, Paul J.; Ives, Stephen J.; Norton, Chelsea; Escudero, Daniela; Minicucci, Olivia; O’Brien, Gabe; Paul, Maia; Ormsbee, Michael J.; Miller, Vincent; Sheridan, Caitlin; He, Feng

    2016-01-01

    The beneficial cardiometabolic and body composition effects of combined protein-pacing (P; 5–6 meals/day at 2.0 g/kg BW/day) and multi-mode exercise (resistance, interval, stretching, endurance; RISE) training (PRISE) in obese adults has previously been established. The current study examines PRISE on physical performance (endurance, strength and power) outcomes in healthy, physically active women. Thirty exercise-trained women (>4 days exercise/week) were randomized to either PRISE (n = 15) or a control (CON, 5–6 meals/day at 1.0 g/kg BW/day; n = 15) for 12 weeks. Muscular strength (1-RM bench press, 1-RM BP) endurance (sit-ups, SUs; push-ups, PUs), power (bench throws, BTs), blood pressure (BP), augmentation index, (AIx), and abdominal fat mass were assessed at Weeks 0 (pre) and 13 (post). At baseline, no differences existed between groups. Following the 12-week intervention, PRISE had greater gains (p < 0.05) in SUs, PUs (6 ± 7 vs. 10 ± 7, 40%; 8 ± 13 vs. 14 ± 12, 43% ∆reps, respectively), BTs (11 ± 35 vs. 44 ± 34, 75% ∆watts), AIx (1 ± 9 vs. −5 ± 11, 120%), and DBP (−5 ± 9 vs. −11 ± 11, 55% ∆mmHg). These findings suggest that combined protein-pacing (P; 5–6 meals/day at 2.0 g/kg BW/day) diet and multi-component exercise (RISE) training (PRISE) enhances muscular endurance, strength, power, and cardiovascular health in exercise-trained, active women. PMID:27258301

  13. Communication: Improved pair approximations in local coupled-cluster methods

    SciTech Connect

    Schwilk, Max; Werner, Hans-Joachim; Usvyat, Denis

    2015-03-28

    In local coupled cluster treatments the electron pairs can be classified according to the magnitude of their energy contributions or distances into strong, close, weak, and distant pairs. Different approximations are introduced for the latter three classes. In this communication, an improved simplified treatment of close and weak pairs is proposed, which is based on long-range cancellations of individually slowly decaying contributions in the amplitude equations. Benchmark calculations for correlation, reaction, and activation energies demonstrate that these approximations work extremely well, while pair approximations based on local second-order Møller-Plesset theory can lead to errors that are 1-2 orders of magnitude larger.

  14. Factors influencing pacing in triathlon

    PubMed Central

    Wu, Sam SX; Peiffer, Jeremiah J; Brisswalter, Jeanick; Nosaka, Kazunori; Abbiss, Chris R

    2014-01-01

    Triathlon is a multisport event consisting of sequential swim, cycle, and run disciplines performed over a variety of distances. This complex and unique sport requires athletes to appropriately distribute their speed or energy expenditure (ie, pacing) within each discipline as well as over the entire event. As with most physical activity, the regulation of pacing in triathlon may be influenced by a multitude of intrinsic and extrinsic factors. The majority of current research focuses mainly on the Olympic distance, whilst much less literature is available on other triathlon distances such as the sprint, half-Ironman, and Ironman distances. Furthermore, little is understood regarding the specific physiological, environmental, and interdisciplinary effects on pacing. Therefore, this article discusses the pacing strategies observed in triathlon across different distances, and elucidates the possible factors influencing pacing within the three specific disciplines of a triathlon. PMID:25258562

  15. Improved measurement of ttZ couplings at the LHC

    SciTech Connect

    Baur, U.; Juste, A.; Rainwater, D.; Orr, L.H.; /Rochester U.

    2005-12-01

    We consider QCD t{bar t}Z production at the LHC with Z {yields} {bar {nu}}{nu} and all-hadronic t{bar t} decays, i.e. pp {yields} p{sub T}b{bar b}+4 jets, as a tool to measure ttZ couplings. This channel has a significantly larger cross section than those where the Z boson decays leptonically. However, t{bar t}, b{bar b} + 4 jet, t{bar t}j and t{bar t}jj production give rise to potentially large backgrounds. We show that these processes can be suppressed to an acceptable level with suitable cuts, and find that adding the p{sub T} b{bar b} + 4 jet channel to the final states used in previous ttZ couplings analyses will improve the sensitivity by 10-60%. We also discuss how the measurement of the ttZ couplings may constrain Little Higgs models.

  16. Historical highlights in cardiac pacing.

    PubMed

    Geddes, L A

    1990-01-01

    The benchmarks in cardiac pacing are identified, beginning with F. Steiner (1871), who rhythmically stimulated the chloroform-arrested hearts of 3 horses, 1 donkey, 10 dogs, 14 cats, and 8 rabbits. The chloroform-arrested heart in human subjects was paced by T. Greene in the following year (1872) in the UK. In 1882, H. Ziemssen in Germany applied cardiac pacing to a 42-year old woman who had a large defect in the anterior left chest wall subsequent to resection of an enchondroma. Intentional cardiac pacing did not occur until 1932, when A.A. Hyman in the US demonstrated that cardiac pacing could be clinically practical. Hyman made a batteryless pacemaker for delivery in induction shock stimuli (60-120/min) to the atria. His pacemaker was powered by a hand-wound, spring-driven generator which provided 6 min of pacemaking without rewinding. Closed-chest ventricular pacing was introduced in the US in 1952 by P.M. Zoll et al. Zoll (1956) also introduced closed-chest ventricular defibrillation. W.L. Weirich et al. (1958) demonstrated that direct-heart stimulation in closed-chest patients could be achieved with slender wire electrodes. S. Furman and J.B. Schwedel (1959) developed a monopolar catheter electrode for ventricular pacing in man. In the same year, W. Greatbatch and W.M. Chardack developed the implantable pacemaker. PMID:18238328

  17. Four chamber pacing in dilated cardiomyopathy.

    PubMed

    Cazeau, S; Ritter, P; Bakdach, S; Lazarus, A; Limousin, M; Henao, L; Mundler, O; Daubert, J C; Mugica, J

    1994-11-01

    A 54-year-old man received a four chamber pacing system for severe congestive heart failure (NYHA functional Class IV). His ECG showed a left bundle branch block (200-msec QRS duration) with 200-msec PR interval, normal QRS axis, and 90-msec interatrial interval. An acute hemodynamic study with insertion of four temporary leads was performed prior to the implant, which demonstrated a significant increase in cardiac output and decrease of pulmonary capillary wedge pressure. A permanent pacemaker was implanted based on the encouraging results of the acute study. The right chamber leads were introduced by cephalic and subclavian approaches. The left atrium was paced with a coronary sinus lead, Medtronic SP 2188-58 model. An epicardial Medtronic 5071 lead was placed on the LV free wall. The four leads were connected to a standard bipolar DDD pacemaker, Chorus 6234. The two atrial leads were connected via a Y-connector to the atrial channel of the pacemaker with a bipolar pacing configuration. The two ventricular leads were connected in a similar fashion to the ventricular channel of the device. The right chamber leads were connected to the distal poles. The left chamber leads were connected to the proximal poles of the pacemaker. Six weeks later, the patient's clinical status improved markedly with a weight loss of 17 kg and disappearance of peripheral edema. His functional class was reduced to NYHA II. Four chamber pacing is technically feasible. In patients with evidence of interventricular dyssynchrony, this original pacing mode probably provides a mechanical activation sequence closer to the natural one.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7845801

  18. Slow Pace for Race to Top Spending

    ERIC Educational Resources Information Center

    McNeil, Michele

    2012-01-01

    Almost two years into the federal Race to the Top program, states are spending their shares of the $4 billion prize at a snail's pace--a reflection of the challenges the 12 winners face as they try to get ambitious education improvement plans off the ground. Through the end of March, the 11 states and the District of Columbia had spent just 14…

  19. Improving the gate fidelity of capacitively coupled spin qubits

    NASA Astrophysics Data System (ADS)

    Wang, Xin; Barnes, Edwin

    2015-03-01

    Precise execution of quantum gates acting on two or multiple qubits is essential to quantum computation. For semiconductor spin qubits coupled via capacitive interaction, the best fidelity for a two-qubit gate demonstrated so far is around 70%, insufficient for fault-tolerant quantum computation. In this talk we present control protocols that may substantially improve the robustness of two-qubit gates against both nuclear noise and charge noise. Our pulse sequences incorporate simultaneous dynamical decoupling protocols and are simple enough for immediate experimental realization. Together with existing control protocols for single-qubit gates, our results constitute an important step toward scalable quantum computation using spin qubits. This work is done in collaboration with Sankar Das Sarma and supported by LPS-NSA-CMTC and IARPA-MQCO.

  20. Optogenetic pacing in Drosophila melanogaster

    PubMed Central

    Alex, Aneesh; Li, Airong; Tanzi, Rudolph E.; Zhou, Chao

    2015-01-01

    Electrical stimulation is currently the gold standard for cardiac pacing. However, it is invasive and nonspecific for cardiac tissues. We recently developed a noninvasive cardiac pacing technique using optogenetic tools, which are widely used in neuroscience. Optogenetic pacing of the heart provides high spatial and temporal precisions, is specific for cardiac tissues, avoids artifacts associated with electrical stimulation, and therefore promises to be a powerful tool in basic cardiac research. We demonstrated optogenetic control of heart rhythm in a well-established model organism, Drosophila melanogaster. We developed transgenic flies expressing a light-gated cation channel, channelrhodopsin-2 (ChR2), specifically in their hearts and demonstrated successful optogenetic pacing of ChR2-expressing Drosophila at different developmental stages, including the larva, pupa, and adult stages. A high-speed and ultrahigh-resolution optical coherence microscopy imaging system that is capable of providing images at a rate of 130 frames/s with axial and transverse resolutions of 1.5 and 3.9 μm, respectively, was used to noninvasively monitor Drosophila cardiac function and its response to pacing stimulation. The development of a noninvasive integrated optical pacing and imaging system provides a novel platform for performing research studies in developmental cardiology. PMID:26601299

  1. Improving Higgs coupling measurements through ZZ Fusion at the ILC

    DOE PAGESBeta

    Han, Tao; Liu, Zhen; Qian, Zhuoni; Sayre, Joshua

    2015-06-17

    In this study, we evaluate the e-e+ → e-e+ + h process through the ZZ fusion channel at the International Linear Collider operating at 500 GeV and 1 TeV center-of-mass energies. We perform realistic simulations on the signal process and background processes. With judicious kinematic cuts, we find that the inclusive cross section can be measured to 2.9% after combining the 500 GeV at 500 fb-1 and 1 TeV at 1 ab-1 runs. A multivariate log-likelihood analysis further improves the precision of the cross section measurement to 2.3%. We discuss the overall improvement to model-independent Higgs width and coupling determinations and demonstrate the usemore » of different channels in distinguishing new physics effects in Higgs physics. Our study demonstrates the importance of the ZZ fusion channel to Higgs precision physics, which has often been neglected in the literature.« less

  2. Improving Higgs coupling measurements through ZZ Fusion at the ILC

    SciTech Connect

    Han, Tao; Liu, Zhen; Qian, Zhuoni; Sayre, Joshua

    2015-06-17

    In this study, we evaluate the e-e+ → e-e+ + h process through the ZZ fusion channel at the International Linear Collider operating at 500 GeV and 1 TeV center-of-mass energies. We perform realistic simulations on the signal process and background processes. With judicious kinematic cuts, we find that the inclusive cross section can be measured to 2.9% after combining the 500 GeV at 500 fb-1 and 1 TeV at 1 ab-1 runs. A multivariate log-likelihood analysis further improves the precision of the cross section measurement to 2.3%. We discuss the overall improvement to model-independent Higgs width and coupling determinations and demonstrate the use of different channels in distinguishing new physics effects in Higgs physics. Our study demonstrates the importance of the ZZ fusion channel to Higgs precision physics, which has often been neglected in the literature.

  3. Obstacles to activity pacing: assessment, relationship to activity and functioning.

    PubMed

    Cane, Douglas; McCarthy, Mary; Mazmanian, Dwight

    2016-07-01

    Activity pacing is frequently included among the strategies provided to individuals with chronic pain to manage pain and improve functioning. Individuals with chronic pain may, however, limit their use of activity pacing because they perceive significant obstacles to its use. This study describes the development of a measure to assess obstacles to activity pacing and examines the relationship of this measure to activity patterns and functioning. A sample of 637 individuals with chronic pain completed items describing potential obstacles to activity pacing as part of their pretreatment assessment. Item analyses were used to construct a 14-item measure of obstacles to activity pacing. A subset of these individuals completed the measure again after completion of a group treatment program. The resulting measure demonstrated excellent internal consistency and was minimally affected by social desirability. Correlations with measures of activity and psychosocial functioning provided initial construct validity for the measure. Sex differences were found with women initially identifying more obstacles to activity pacing. Fewer obstacles were identified by both men and women after treatment, and these changes were related to modest changes in activity patterns and functioning. The present results identify a number of obstacles that may limit the use of activity pacing by individuals with chronic pain. Treatment may result in a decrease in the number of obstacles identified, and this change is related to changes in the individual's activity pattern and psychosocial functioning. PMID:26963845

  4. Diaphragm pacing: the state of the art

    PubMed Central

    Legras, Antoine; Arame, Alex; Pricopi, Ciprian; Boucherie, Jean-Claude; Badia, Alain; Panzini, Capucine Morelot

    2016-01-01

    Diaphragm pacing (DP) is an orphan surgical procedure that may be proposed in strictly selected ventilator-dependent patients to get an active diaphragm contraction. The goal is to wean from mechanical ventilation (MV) and restore permanent efficient breathing. The two validated indications, despite the lack of randomised control trials, concern patients with high-level spinal cord injuries (SCI) and central hypoventilation syndromes (CHS). To date, two different techniques exist. The first, intrathoracic diaphragm pacing (IT-DP), based on a radiofrequency method, in which the electrodes are directly placed around the phrenic nerve. The second, intraperitoneal diaphragm pacing (IP-DP) uses intradiaphragmatic electrodes implanted through laparoscopy. In both techniques, the phrenic nerves must be intact and diaphragm reconditioning is always required after implantation. No perioperative mortality has been reported and ventilator-weaning rate is about 72% to 96% in both techniques. Improvement of quality of life, by restoring a more physiological breathing, has been almost constant in patients that could be weaned. Failure or delay in recovery of effective diaphragm contractions could be due to irreversible amyotrophy or chest wall damage. Recent works have evaluated the interest of IP-DP in amyotrophic lateral sclerosis (ALS). After some short series were reported in the literature, the only multicentric randomized study including 74 ALS patients was prematurely stopped because of excessive mortality in paced patients. Then, another trial analysed the place of IP-DP in peripheral diaphragm dysfunction but, given the multiple biases, the published results cannot validate that indication. Reviewing all available literature as in our experience, shows that DP is an effective method to wean selected patients dependent on ventilator and improve their daily life. Other potential indications will have to be evaluated by randomised control trials. PMID:27195135

  5. Diaphragm pacing: the state of the art.

    PubMed

    Le Pimpec-Barthes, Francoise; Legras, Antoine; Arame, Alex; Pricopi, Ciprian; Boucherie, Jean-Claude; Badia, Alain; Panzini, Capucine Morelot

    2016-04-01

    Diaphragm pacing (DP) is an orphan surgical procedure that may be proposed in strictly selected ventilator-dependent patients to get an active diaphragm contraction. The goal is to wean from mechanical ventilation (MV) and restore permanent efficient breathing. The two validated indications, despite the lack of randomised control trials, concern patients with high-level spinal cord injuries (SCI) and central hypoventilation syndromes (CHS). To date, two different techniques exist. The first, intrathoracic diaphragm pacing (IT-DP), based on a radiofrequency method, in which the electrodes are directly placed around the phrenic nerve. The second, intraperitoneal diaphragm pacing (IP-DP) uses intradiaphragmatic electrodes implanted through laparoscopy. In both techniques, the phrenic nerves must be intact and diaphragm reconditioning is always required after implantation. No perioperative mortality has been reported and ventilator-weaning rate is about 72% to 96% in both techniques. Improvement of quality of life, by restoring a more physiological breathing, has been almost constant in patients that could be weaned. Failure or delay in recovery of effective diaphragm contractions could be due to irreversible amyotrophy or chest wall damage. Recent works have evaluated the interest of IP-DP in amyotrophic lateral sclerosis (ALS). After some short series were reported in the literature, the only multicentric randomized study including 74 ALS patients was prematurely stopped because of excessive mortality in paced patients. Then, another trial analysed the place of IP-DP in peripheral diaphragm dysfunction but, given the multiple biases, the published results cannot validate that indication. Reviewing all available literature as in our experience, shows that DP is an effective method to wean selected patients dependent on ventilator and improve their daily life. Other potential indications will have to be evaluated by randomised control trials. PMID:27195135

  6. Presentation Time Concerning System-Paced Multimedia Instructions and the Superiority of Learner Pacing

    ERIC Educational Resources Information Center

    Stiller, Klaus D.; Petzold, Kirstin; Zinnbauer, Peter

    2011-01-01

    The superiority of learner-paced over system-paced instructions was demonstrated in multiple experiments. In these experiments, the system-paced presentations were highly speeded, causing cognitive overload, while the learner-paced instructions allowed adjustments of the presentational flow to the learner's needs by pacing facilities, mostly…

  7. Improvements in Representations of Cloud Microphysics for BBHRP and Models using Data Collected during M-PACE and TWP-ICE

    SciTech Connect

    Greg M. McFarquhar

    2010-02-22

    In our research we proposed to use data collected during the 2004 Mixed-Phase Arctic Cloud Experiment (MPACE) and the 2006 Tropical Warm Pool International Cloud Experiment (TWP-ICE) to improve retrievals of ice and mixed-phase clouds, to improve our understanding of how cloud and radiative processes affect cloud life cycles, and to develop and test methods for using ARM data more effectively in model. In particular, we proposed to: 1) use MPACE in-situ data to determine how liquid water fraction and cloud ice and liquid effective radius (r{sub ei} and r{sub ew}) vary with temperature, normalized cloud altitude and other variables for Arctic mixed-phase clouds, and to use these data to evaluate the performance of model parameterization schemes and remote sensing retrieval algorithms; 2) calculate rei and size/shape distributions using TWP-ICE in-situ data, investigate their dependence on cirrus type (oceanic or continental anvils or cirrus not directly traced to convection), and develop and test representations for MICROBASE; 3) conduct fundamental research enhancing our understanding of cloud/radiative interactions, concentrating on effects of small crystals and particle shapes and sizes on radiation; and 4) improve representations of microphysical processes for models (fall-out, effective density, mean scattering properties, rei and rew) and provide them to ARM PIs. In the course of our research, we made substantial progress on all four goals.

  8. Improving the calculation of magnetic coupling constants in MRPT methods.

    PubMed

    Spivak, Mariano; Angeli, Celestino; Calzado, Carmen J; de Graaf, Coen

    2014-09-01

    The magnetic coupling in transition metal compounds with more than one unpaired electron per magnetic center has been studied with multiconfigurational perturbation theory. The usual shortcomings of these methodologies (severe underestimation of the magnetic coupling) have been overcome by describing the Slater determinants with a set of molecular orbitals that maximally resemble the natural orbitals of a high-level multiconfigurational reference configuration interaction calculation. These orbitals have significant delocalization tails onto the bridging ligands and largely increase the coupling strengths in the perturbative calculation. PMID:24992654

  9. Science Unit Plans. PACE '94.

    ERIC Educational Resources Information Center

    Schoon, Kenneth J., Ed.; Wiles, Clyde A., Ed.

    This booklet contains mathematics unit plans for Biology, Chemistry, and Physical Science developed by PACE (Promoting Academic Excellence In Mathematics, Science & Technology for Workers of the 21st Century). Each unit plan contains suggested timing, objectives, skills to be acquired, workplace relationships, learning activities with suggested…

  10. Mathematics Unit Plans. PACE '94.

    ERIC Educational Resources Information Center

    Wiles, Clyde A., Ed.; Schoon, Kenneth J., Ed.

    This booklet contains mathematics unit plans for Algebra 1, Geometry, Math for Technology, Mathematical Problem Solving, and Pre-Algebra developed by PACE (Promoting Academic Excellence In Mathematics, Science & Technology for Workers of the 21st Century). Each unit plan contains suggested timing, objectives, skills to be acquired, workplace…

  11. Diaphragmatic pacing in spinal cord injury.

    PubMed

    Dalal, Kevin; DiMarco, Anthony F

    2014-08-01

    After cervical spinal cord injuries, many patients are unable to sustain independent ventilation because of a disruption of diaphragm innervation and respiratory functioning. If phrenic nerve function is preserved, the patient may be able to tolerate exogenous pacing of the diaphragm via electrical stimulation. Previously this was accomplished by stimulation directly to the phrenic nerves, but may be accomplished less invasively by percutaneously stimulating the diaphragm itself. The benefits, when compared with mechanical ventilation, include a lower rate of pulmonary complications, improved venous return, more normal breathing and speech, facilitation of eating, cost-effectiveness, and increased patient mobility. PMID:25064791

  12. Did recent world record marathon runners employ optimal pacing strategies?

    PubMed

    Angus, Simon D

    2014-01-01

    We apply statistical analysis of high frequency (1 km) split data for the most recent two world-record marathon runs: Run 1 (2:03:59, 28 September 2008) and Run 2 (2:03:38, 25 September 2011). Based on studies in the endurance cycling literature, we develop two principles to approximate 'optimal' pacing in the field marathon. By utilising GPS and weather data, we test, and then de-trend, for each athlete's field response to gradient and headwind on course, recovering standardised proxies for power-based pacing traces. The resultant traces were analysed to ascertain if either runner followed optimal pacing principles; and characterise any deviations from optimality. Whereas gradient was insignificant, headwind was a significant factor in running speed variability for both runners, with Runner 2 targeting the (optimal) parallel variation principle, whilst Runner 1 did not. After adjusting for these responses, neither runner followed the (optimal) 'even' power pacing principle, with Runner 2's macro-pacing strategy fitting a sinusoidal oscillator with exponentially expanding envelope whilst Runner 1 followed a U-shaped, quadratic form. The study suggests that: (a) better pacing strategy could provide elite marathon runners with an economical pathway to significant performance improvements at world-record level; and (b) the data and analysis herein is consistent with a complex-adaptive model of power regulation. PMID:23879745

  13. Two-channel gastric pacing in patients with diabetic gastroparesis

    PubMed Central

    Lin, Zhiyue; Sarosiek, Irene; Forster, Jameson; Ross, Robert A.; Chen, Jiande D.Z.; McCallum, Richard W.

    2011-01-01

    Background Our primary goals were to investigate the effects of two-channel gastric pacing on gastric myoelectrical activity, and energy consumption with the secondary intent to monitor gastric emptying and symptoms in patients with severe diabetic gastroparesis. Methods Four pairs of temporary pacing wires were inserted on the serosa of the stomach at the time of laparotomy to place the Enterra™ System in 19 patients with severe gastroparesis not responding to standard medical therapies. Two of the pairs were for electrical stimulation and the other two for recording. Five days after surgery the optimal pacing parameters for the entrainment of gastric slow waves in each patient were identified by serosal recordings. Two-channel gastric pacing was then initiated for 6 weeks using a newly developed external multi-channel pulse generator. Electrogastrogram (EGG), total symptom score (TSS), and a 4-hour gastric emptying test were assessed at baseline and after 6 weeks of active gastric pacing. Enterra™ device was turned OFF during the duration of this study. Key Results Two-channel gastric pacing at 1.1 times the intrinsic frequency entrained gastric slow waves and normalized gastric dysrhythmia. After 6 weeks of gastric pacing, tachygastria was decreased from 15±3 to 5±1% in the fasting state and from 10±2 to 5±1% postprandially (P<0.05), mean TSS was reduced from 21.3±1.1 to 7.0±1.5 (P<0.05) and mean 4-hour gastric retention improved from 42% to 28% (P=0.05). Conclusions& Inferences Two-channel gastric pacing is a novel treatment approach which is able to normalize and enhance gastric slow wave activity as well as accelerate gastric emptying in patients with diabetic gastroparesis with a good safety profile. PMID:21806741

  14. Pacing the Heart with Genes: Recent Progress in Biological Pacing.

    PubMed

    Cho, Hee Cheol

    2015-08-01

    The heartbeat originates within the sinoatrial node (SA node or SAN), a small highly specialized structure containing <10,000 genuine pacemaker cells. The ~5 billion working cardiomyocytes downstream of the SAN remain quiescent when it fails, leading to circulatory collapse and fueling a $6B/year electronic pacemaker industry. The electronic pacemaker devices work quite well. But, device-related problems persist. These include lead failure/repositioning, finite battery life, and infection. For pediatric patients, the children outgrow the length of the leads, necessitating replacement with longer leads. These pitfalls have motivated creation of biological pacing. that are free from all hardware. Toward this goal, we and others have tested the concept of biological pacemakers. Combined with efforts to create clinically relevant, large animal models of biological pacing, the field is moving beyond a conceptual novelty toward a future with clinical reality. PMID:26116393

  15. Self-Paced Instruction: A Review

    ERIC Educational Resources Information Center

    Allison, Elisabeth

    1975-01-01

    Discussed the benefits and costs of self-paced instruction (SPI) based on brief summaries of experiences in teaching introductory economics at seven universities. Provided also is a six-step pattern for setting up a self-paced course. The author concludes that the evidence on the educational benefits of self-paced instruction is at present…

  16. 42 CFR 460.186 - PACE premiums.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 4 2012-10-01 2012-10-01 false PACE premiums. 460.186 Section 460.186 Public...) Payment § 460.186 PACE premiums. The amount that a PACE organization can charge a participant as a monthly premium depends on the participant's eligibility under Medicare and Medicaid, as follows: (a)...

  17. MHD generator with improved network coupling electrodes to a load

    DOEpatents

    Rosa, Richard J.

    1977-01-01

    An MHD generator has a plurality of segmented electrodes extending longitudinally of a duct, whereby progressively increasing high DC voltages are derived from a set of cathode electrodes and progressively increasing low DC voltages are derived from a set of anode electrodes. First and second load terminals are respectively connected to the cathode and anode electrodes by separate coupling networks, each of which includes a number of SCR's and a number of diode rectifiers.

  18. Pacing the right ventricular outflow tract septum: time to embrace the future.

    PubMed

    Hillock, Richard J; Mond, Harry G

    2012-01-01

    Transvenous pacing has revolutionized the management of patients with potentially life-threatening bradycardias and at its most basic level ensures rate support to maintain cardiac output. However, we have known for at least a decade that pacing from the right ventricle (RV) apex can induce left ventricle (LV) dysfunction, atrial fibrillation, heart failure, and maybe an increased mortality. Although pacemaker manufacturers have developed successful pacing algorithms designed to minimize unnecessary ventricular pacing, it cannot be avoided in a substantial proportion of pacemaker-dependent patients. Just as there is undoubted evidence that RV apical pacing is injurious, there is emerging evidence that pacing from the RV septum is associated with a shorter duration of activation, improved haemodynamics, and less LV remodelling. The move from traditional RV apical pacing to RV septal pacing requires a change in mindset for many practitioners. The anatomical landmarks and electrocardiograph features of RV septal pacing are well described and easily recognized. While active fixation is required to place the lead on the septum, shaped stylets are now available to assist the implanter. In addition, concerns about the stability and longevity of steroid-eluting active fixation leads have proven to be unfounded. We therefore encourage all implanters to adopt RV septal pacing to minimize the potential of harm to their patients. PMID:21846639

  19. DDD pacing in hypertrophic cardiomyopathy: a multicentre clinical experience.

    PubMed Central

    Slade, A. K.; Sadoul, N.; Shapiro, L.; Chojnowska, L.; Simon, J. P.; Saumarez, R. C.; Dodinot, B.; Camm, A. J.; McKenna, W. J.; Aliot, E.

    1996-01-01

    BACKGROUND--DDD pacing has been advocated as an effective treatment for drug refractory obstructive hypertrophic cardiomyopathy. This study reports the outcome of pacing in 56 patients with refractory symptoms referred to four tertiary centres. METHODS--Core data on symptoms, drug burden, and left ventricular outflow tract gradient were recorded. Patients underwent a temporary pacing study with optimisation of the atrioventricular (AV) delay for greatest gradient reduction without haemodynamic compromise. Patients were assessed after implantation in terms of changes in symptoms, drug load, and outflow tract gradient. RESULTS--56 patients underwent pacing assessment. The mean (SD) left ventricular outflow tract gradient before pacing was 78 (31) mm Hg. At temporary study the mean (SD) left ventricular outflow tract gradient was 38 (24) mm Hg with a median (range) optimised sensed AV delay of 65 (25-125) ms. Fifty three patients were implanted and followed up for a mean (SD) of 11 (11) months. The median (range) programmed sensed AV delay was 60 (31-200) ms. Left ventricular outflow tract gradient at follow up was 36 (25) mm Hg. Forty four patients had improved functional class. Although a correlation (r = 0.69) was shown between acute and chronic left ventricular outflow tract gradient reduction, there was no correlation between magnitude of gradient reduction and functional improvement, and no appreciable change in pharmacological burden. CONCLUSION--This series confirms symptomatic improvement after DDD pacing in hypertrophic cardiomyopathy. There remains, however, a discrepancy between perceived symptomatic benefit and modest objective improvement. Furthermore, the optimal outcome has been achieved only with continued pharmacological treatment. Current methods of temporary evaluation do not predict functional outcome which seems to be independent of the magnitude of gradient reduction. PMID:8624871

  20. Optical pacing of the adult rabbit heart.

    PubMed

    Jenkins, Michael W; Wang, Y T; Doughman, Y Q; Watanabe, M; Cheng, Y; Rollins, A M

    2013-01-01

    Optical pacing has been demonstrated to be a viable alternative to electrical pacing in embryonic hearts. In this study, the feasibility of optically pacing an adult rabbit heart was explored. Hearts from adult New Zealand White rabbits (n = 9) were excised, cannulated and perfused on a modified Langendorff apparatus. Pulsed laser light (λ = 1851 nm) was directed to either the left or right atrium through a multimode optical fiber. An ECG signal from the left ventricle and a trigger pulse from the laser were recorded simultaneously to determine when capture was achieved. Successful optical pacing was demonstrated by obtaining pacing capture, stopping, then recapturing as well as by varying the pacing frequency. Stimulation thresholds measured at various pulse durations suggested that longer pulses (8 ms) had a lower energy capture threshold. To determine whether optical pacing caused damage, two hearts were perfused with 30 µM of propidium iodide and analyzed histologically. A small number of cells near the stimulation site had compromised cell membranes, which probably limited the time duration over which pacing was maintained. Here, short-term optical pacing (few minutes duration) is demonstrated in the adult rabbit heart for the first time. Future studies will be directed to optimize optical pacing parameters to decrease stimulation thresholds and may enable longer-term pacing. PMID:24049683

  1. 42 CFR 460.60 - PACE organizational structure.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PACE Administrative Requirements § 460.60 PACE organizational structure. (a) A...

  2. 42 CFR 460.34 - Duration of PACE program agreement.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PACE Program Agreement § 460.34 Duration of PACE program agreement. An agreement...

  3. 42 CFR 460.34 - Duration of PACE program agreement.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PACE Program Agreement § 460.34 Duration of PACE program agreement. An agreement...

  4. 42 CFR 460.34 - Duration of PACE program agreement.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PACE Program Agreement § 460.34 Duration of PACE program agreement. An agreement...

  5. 42 CFR 460.60 - PACE organizational structure.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PACE Administrative Requirements § 460.60 PACE organizational structure. (a) A...

  6. 42 CFR 460.60 - PACE organizational structure.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PACE Administrative Requirements § 460.60 PACE organizational structure. (a) A...

  7. 42 CFR 460.34 - Duration of PACE program agreement.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PACE Program Agreement § 460.34 Duration of PACE program agreement. An agreement...

  8. 42 CFR 460.60 - PACE organizational structure.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PACE Administrative Requirements § 460.60 PACE organizational structure. (a) A...

  9. 42 CFR 460.34 - Duration of PACE program agreement.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PACE Program Agreement § 460.34 Duration of PACE program agreement. An agreement...

  10. 42 CFR 460.60 - PACE organizational structure.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PACE Administrative Requirements § 460.60 PACE organizational structure. (a) A...

  11. Entanglement of Coupled Optomechanical Systems Improved by Optical Parametric Amplifiers

    NASA Astrophysics Data System (ADS)

    Pan, Guixia; Xiao, Ruijie; Zhou, Ling

    2016-04-01

    A scheme to generate the stationary entanglement of two distant coupled optical cavities placed optical parametric amplifiers is proposed. We study how the optical parametric amplifiers can affect the entanglement behaviors of the movable mirrors and the cavity fields. With the existence of optical parametric amplifiers, we show that larger stationary entanglement of optical and mechanical modes can be obtained and the entanglement increases with the increasing parametric gain. Especially, the degree of entanglement between the two cavity fields is more pronouncedly enhanced. Moreover, for a fixed parametric gain, the entanglement of distant cavity optomechanical systems increases as the input laser power is increased.

  12. Entanglement of Coupled Optomechanical Systems Improved by Optical Parametric Amplifiers

    NASA Astrophysics Data System (ADS)

    Pan, Guixia; Xiao, Ruijie; Zhou, Ling

    2016-08-01

    A scheme to generate the stationary entanglement of two distant coupled optical cavities placed optical parametric amplifiers is proposed. We study how the optical parametric amplifiers can affect the entanglement behaviors of the movable mirrors and the cavity fields. With the existence of optical parametric amplifiers, we show that larger stationary entanglement of optical and mechanical modes can be obtained and the entanglement increases with the increasing parametric gain. Especially, the degree of entanglement between the two cavity fields is more pronouncedly enhanced. Moreover, for a fixed parametric gain, the entanglement of distant cavity optomechanical systems increases as the input laser power is increased.

  13. Cardiac Pacing - Is Telemonitoring Now Essential?

    PubMed

    Burri, Haran

    2013-11-01

    Modern pacemakers and implantable defibrillators are able to automatically perform tests executed manually during in-office visits; such as measurement of sensing and pacing thresholds. In addition, the devices also record a wealth of diagnostic data that are of clinical relevance. The advent of wireless technology in these devices allows automatic transmission of these data that can be consulted remotely by the physician. There is now solid evidence indicating that remote device follow-up can safely reduce the number of in-office visits, thereby improving convenience for patients and caregivers alike. Remote monitoring with automatic alerts for arrhythmias, heart failure and technical issues, has been shown to dramatically reduce delay to diagnosis of these events compared with standard follow-up; potentially improving patient safety and outcome. For these reasons, remote device management is becoming the standard of care. PMID:26835047

  14. [Permanent cardiac pacing in women--light and shadow].

    PubMed

    Małecka, Barbara; Wysokińsk, Andrzej

    2015-01-01

    Permanent cardiac pacing has survived a sharp increase in quality improvement and frequency of usage. Nowadays particular aspects of this method of treatment are being considered. In this paper distinctiveness of women population treated by permanent pacing is discussed. Indications for heart pacing in women appear at a later age than in men. Moreover, women remain longer in follow-up, therefore their prognosis is better. The most serious late pacing complications, i.e., infections are less frequent in women. However, implantations procedures seem to be more difficult in female gender, most probably due to a smaller body size, especially of afferent veins. This leads to a higher periprocedural complication rate and refers especially to endocardial lead implantation, which in women is connected with double risk of pneumothorax. Late complications of permanent pacing are effectively treated by transvenous lead extraction. Female gender has been demonstrated as an independent risk factor of extraction failure. It seems that reasonable qualification for pacemaker implantations and leaving the procedures in the hands of experienced operators will strengthen the "light side" and limit the "dark side" of this therapy in women. PMID:26455022

  15. Tools and Trends in Self-Paced Language Instruction

    ERIC Educational Resources Information Center

    Godwin-Jones, Robert

    2007-01-01

    Ever since the PLATO system of the 1960's, CALL (computer assisted language learning) has had a major focus on providing self-paced, auto-correcting exercises for language learners to practice their skills and improve their knowledge of discrete areas of language learning. The computer has been recognized from the beginning as a patient and…

  16. Improved Fiber-Optic-Coupled Pressure And Vibration Sensors

    NASA Technical Reports Server (NTRS)

    Zuckerwar, Allan J.; Cuomo, Frank W.

    1994-01-01

    Improved fiber-optic coupler enables use of single optical fiber to carry light to and from sensor head. Eliminates problem of alignment of multiple fibers in sensor head and simplifies calibration by making performance both more predictable and more stable. Sensitivities increased, sizes reduced. Provides increased margin for design of compact sensor heads not required to contain amplifier circuits and withstand high operating temperatures.

  17. Improvement of uniformity in a weakly magnetized inductively coupled plasma

    NASA Astrophysics Data System (ADS)

    Lee, W. H.; Cheong, H. W.; Kim, J. W.; Whang, K. W.

    2015-12-01

    Magnetic fields are applied to inductively coupled plasma (ICP) to achieve high plasma densities using electromagnets. If the magnetic fields are set up such that the magnitude of magnetic flux density on the substrate decreases with both radial and axial distances from the substrate’s center (here after referred to as M-ICP-A), the plasma density increases by 237% compared with that for ICP although the non-uniformity of the plasma density for M-ICP-A (11.1%) is higher than that for ICP (10.9%). As the rate of decrease in the magnitude of magnetic flux density on the substrate increases both radially and axially, the non-uniformity in the plasma density increases further. The increase in the non-uniformity for M-ICP-A was confirmed to arise from the flute instability. To suppress the flute instability, we arranged the magnitude of magnetic flux density on the substrate to increase with increasing distance from the substrate center both radially and axially (here after referred to as M-ICP-V). In this configuration, plasma fluctuations were not observed, hence the plasma density non-uniformity was lowered to 8.1%, although the measured plasma density was higher than that for M-ICP-A. The oxide etch-rate non-uniformity in M-ICP-V (2.5%) was also lower than that for ICP (5.2%) or that for M-ICP-A (21.4%).

  18. Use of Data to Improve Seasonal-to-Interannual Forecasts Simulated by Intermediate Coupled Models

    NASA Technical Reports Server (NTRS)

    Perigaud, C.; Cassou, C.; Dewitte, B.; Fu, L-L.; Neelin, J.

    1999-01-01

    This paper provides a detailed illustration that it can be much more beneficial for ENSO forecasting to use data to improve the model parameterizations rather than to modify the initial conditions to gain in consistency with the simulated coupled system.

  19. Innovative pacing: Recent advances, emerging technologies, and future directions in cardiac pacing.

    PubMed

    Austin, Christopher; Kusumoto, Fred

    2016-07-01

    The field of cardiovascular medicine is rapidly evolving as advancements in technology and engineering provide clinicians new and exciting ways to care for an aging population. Cardiac pacing, in particular, has seen a series of game-changing technologies emerge in the past several years spurred by low-power electronics, high density batteries, improved catheter delivery systems and innovative software design. We look at several of these emerging pacemaker technologies, discussing the rationale, current state and future directions of these pioneering developments in electrophysiology. PMID:27017442

  20. Thallium cardiac stressing by esophageal pacing

    SciTech Connect

    Allen, M.L.; Vacek, J.L.; Preston, D.F.; Robinson, R.G.; Feldkamp, M.J. )

    1989-09-01

    Forty-three patients were examined with the transesophageal pacing method of cardiac stressing and thallium imaging. Transesophageal cardiac pacing, using a pill electrode or a permanent pacemaker lead, is a safe alternative for patients who are physically unable to exercise. Prior studies suggest that transvenous right atrial pacing with thallium injection is equivalent to physical exercise thallium studies in the detection of coronary artery disease. The esophageal pacing bipolar electrode similarly increases heart rate without the necessity of transvenous pacing or fluoroscopy and without the adverse side effects often seen when using pharmacologic stressing agents (i.e., dipyridamole). The results compare well with cardiac catheterization, echocardiographic, and electrocardiographic results. Cardiac paced stress testing requires no sedation, is performed on an out-patient basis, and causes little if any discomfort for the patient.

  1. Finite element analysis of sucker rod couplings with guidelines for improving fatigue life

    SciTech Connect

    Hoffman, E.L.

    1997-09-01

    The response of a variety of sucker rod couplings to an applied axial load was simulated using axisymmetric finite element models. The calculations investigated three sucker rod sizes and various combinations of the slimhole, Spiralock, and Flexbar modifications to the coupling. In addition, the effect of various make-ups (assembly tightness) on the performance of coupling was investigated. An axial load was applied to the sucker rod ranging from {minus}5 ksi to 40 ksi, encompassing three load cycles identified on a modified Goodman diagram as acceptable for indefinite service life of the sucker rods. The simulations of the various coupling geometries and make-ups were evaluated with respect to how well they accomplish the two primary objectives of preloading threaded couplings: (1) to lock the threaded coupling together so that it will not loosen and eventually uncouple, and (2) to improve the fatigue resistance of the threaded connection by reducing the stress amplitude in the coupling when subjected to cyclic loading. Perhaps the most significant finding in this study was the characterization of the coupling parameters which affect two stress measures. The mean hydrostatic stress, which determines the permissible effective alternating stress, is a function of the coupling make-up. Whereas, the alternating effective stress is a function of the relative stiffnesses of the pin and box sections of the coupling and, as long as the coupling does not separate, is unaffected by the amount of circumferential displacement applied during make-up. The results of this study suggest approaches for improving the fatigue resistance of sucker rod couplings.

  2. The effects of fluid ingestion on free-paced intermittent-sprint performance and pacing strategies in the heat.

    PubMed

    Skein, Melissa; Duffield, Rob

    2010-02-01

    The purpose of this study was to examine the effects of fluid ingestion on pacing strategies and performance during intermittent-sprint exercise in the heat. Nine male rugby players performed a habituation session and 2 x 50-min intermittent-sprint protocols at a temperature of 31 degrees C, either with or without fluid. Participants were informed of a third session (not performed) to ensure that they remained blind to all respective conditions. The protocol consisted of a 15-m sprint every minute separated by self-paced bouts of hard running, jogging, and walking for the remainder of the minute. Sprint time, distance covered during self-paced exercise, and vertical jump height before and after exercise were recorded. Heart rate, core temperature, nude mass, capillary blood haematocrit, pH, lactate concentration, perceptual ratings of perceived exertion, thermal stress, and thirst were also recorded. Sprint times (fluid vs. no-fluid: 2.82 +/- 0.11 vs. 2.82 +/- 0.14) and distance covered during self-paced exercise (fluid vs. no-fluid: 4168 +/- 419 vs. 3981 +/- 263 m) were not different between conditions (P = 0.10-0.98) but were progressively reduced to a greater extent in the no-fluid trial (7 +/- 13%) (d = 0.56-0.58). There were no differences (P = 0.22-1.00; d = <0.20-0.84) between conditions in any physiological measures. Perceptual ratings of perceived exertion and thermal stress did not differ between conditions (P = 0.34-0.91; d < or =0.20-0.48). Rating of thirst after exercise was lower in the fluid trial (P = 0.02; d = 0.62-0.73). The present results suggest that fluid availability did not improve intermittent-sprint performance, however did affect pacing strategies with a greater reduction in distance covered of self-paced exercise during the no-fluid trial. PMID:20077276

  3. 42 CFR 460.186 - PACE premiums.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 4 2014-10-01 2014-10-01 false PACE premiums. 460.186 Section 460.186 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY...

  4. 42 CFR 460.186 - PACE premiums.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 4 2013-10-01 2013-10-01 false PACE premiums. 460.186 Section 460.186 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY...

  5. 42 CFR 460.186 - PACE premiums.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 4 2011-10-01 2011-10-01 false PACE premiums. 460.186 Section 460.186 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY...

  6. Web Tools: Keeping Learners on Pace

    ERIC Educational Resources Information Center

    Kosloski, Mickey

    2016-01-01

    One of the greatest challenges in teaching technology and engineering is pacing. Some students grasp new technological concepts quickly, while others need repetition and may struggle to keep pace. This poses an obstacle for the technology and engineering teacher, and is particularly true when teaching students to build a website. However, there…

  7. Consistency of Students' Pace in Online Learning

    ERIC Educational Resources Information Center

    Hershkovitz, Arnon; Nachmias, Rafi

    2009-01-01

    The purpose of this study is to investigate the consistency of students' behavior regarding their pace of actions over sessions within an online course. Pace in a session is defined as the number of logged actions divided by session length (in minutes). Log files of 6,112 students were collected, and datasets were constructed for examining pace…

  8. Effect of Right Ventricular versus Biventricular Pacing on Electrical Remodeling in the Normal Heart

    PubMed Central

    Saba, Samir; Mehdi, Haider; Mathier, Michael A.; Islam, M. Zahadul; Salama, Guy; London, Barry

    2010-01-01

    Background Biventricular (BIV) pacing can improve cardiac function in heart failure by altering the mechanical and electrical substrates. We investigated the effect of BIV versus right ventricular (RV) pacing on the normal heart. Methods and Results Male New Zealand White rabbits (n=33) were divided into 3 groups: sham-operated (control), RV pacing, and BIV pacing groups. Four weeks after surgery, the native QT (p=0.004) interval was significantly shorter in the BIV group compared to the RV or sham-operated groups. Also, compared to rabbits in the RV group, rabbits in the BIV group had shorter RV ventricular effective refractory period (VERP) at all cycle lengths, and shorter LV paced QT interval during the drive train of stimuli and close to refractoriness (p<0.001 for all comparisons). Protein expression of the KVLQT1 was significantly increased in the BIV group compared to the RV and control groups, while protein expression of SCN5A and connexin43 was significantly decreased in the RV compared to the other study groups. Erg protein expression was significantly increased in both pacing groups compared to the controls. Conclusions In this rabbit model, we demonstrate a direct effect of BIV but not RV pacing on shortening the native QT interval as well as the paced QT interval during burst pacing and close to the VERP. These findings underscore the fact that the effect of BIV pacing is partially mediated through direct electrical remodeling and may have implications as to the effect of BIV pacing on arrhythmia incidence and burden. PMID:20042767

  9. Right ventricular septal pacing: Safety and efficacy in a long term follow up

    PubMed Central

    Occhetta, Eraldo; Quirino, Gianluca; Baduena, Lara; Nappo, Rosaria; Cavallino, Chiara; Facchini, Emanuela; Pistelli, Paolo; Magnani, Andrea; Bortnik, Miriam; Francalacci, Gabriella; Dell’Era, Gabriele; Plebani, Laura; Marino, Paolo

    2015-01-01

    AIM: To evaluate the safety and efficacy of the permanent high interventricular septal pacing in a long term follow up, as alternative to right ventricular apical pacing. METHODS: We retrospectively evaluated: (1) 244 patients (74 ± 8 years; 169 men, 75 women) implanted with a single (132 pts) or dual chamber (112 pts) pacemaker (PM) with ventricular screw-in lead placed at the right ventricular high septal parahisian site (SEPTAL pacing); (2) 22 patients with permanent pacemaker and low percentage of pacing (< 20%) (NO pacing); (3) 33 patients with high percentage (> 80%) right ventricular apical pacing (RVA). All patients had a narrow spontaneous QRS (101 ± 14 ms). We evaluated New York Heart Association (NYHA) class, quality of life (QoL), 6 min walking test (6MWT) and left ventricular function (end-diastolic volume, LV-EDV; end-systolic volume, LV-ESV; ejection fraction, LV-EF) with 2D-echocardiography. RESULTS: Pacing parameters were stable during follow up (21 mo/patient). In SEPTAL pacing group we observed an improvement in NYHA class, QoL score and 6MWT. While LV-EDV didn’t significantly increase (104 ± 40 mL vs 100 ± 37 mL; P = 0.35), LV-ESV slightly increased (55 ± 31 mL vs 49 ± 27 mL; P = 0.05) and LV-EF slightly decreased (49% ± 11% vs 53% ± 11%; P = 0.001) but never falling < 45%. In the RVA pacing control group we observed a worsening of NYHA class and an important reduction of LV-EF (from 56% ± 6% to 43% ± 9%, P < 0.0001). CONCLUSION: Right ventricular permanent high septal pacing is safe and effective in a long term follow up evaluation; it could be a good alternative to the conventional RVA pacing in order to avoid its deleterious effects. PMID:26322189

  10. Improvement of bias stability for a micromachined gyroscope based on dynamic electrical balancing of coupling stiffness

    NASA Astrophysics Data System (ADS)

    Su, Jianbin; Xiao, Dingbang; Wu, Xuezhong; Hou, Zhanqiang; Chen, Zhihua

    2013-07-01

    We present a dynamic electrical balancing of coupling stiffness for improving the bias stability of micromachined gyroscopes, which embeds the coupling stiffness in a closed-loop system to make the micromachined gyroscope possess more robust bias stability by suppressing the variation of coupling stiffness. The effect of the dynamic electrical balancing control is theoretically analyzed and implemented using a silicon micromachined gyroscope as an example case. It has been experimentally shown that, comparing with open loop detection, the proposed method increased the stability of the amplitude of the mechanical quadrature signal by 38 times, and therefore improved the bias stability by 5.2 times from 89 to 17 deg/h, and the temperature stability of scale factor by 2.7 times from 622 to 231 ppm/°C. Experimental results effectively indicated the theoretical model of dynamic electrical balancing of coupling stiffness.

  11. COUPLING

    DOEpatents

    Hawke, B.C.

    1963-02-26

    This patent relates to a releasable coupling connecting a control rod to a control rod drive. This remotely operable coupling mechanism can connect two elements which are laterally and angviarly misaligned, and provides a means for sensing the locked condition of the elements. The coupling utilizes a spherical bayonet joint which is locked against rotation by a ball detent lock. (AEC)

  12. The Pace of Cultural Evolution

    PubMed Central

    Perreault, Charles

    2012-01-01

    Today, humans inhabit most of the world’s terrestrial habitats. This observation has been explained by the fact that we possess a secondary inheritance mechanism, culture, in addition to a genetic system. Because it is assumed that cultural evolution occurs faster than biological evolution, humans can adapt to new ecosystems more rapidly than other animals. This assumption, however, has never been tested empirically. Here, I compare rates of change in human technologies to rates of change in animal morphologies. I find that rates of cultural evolution are inversely correlated with the time interval over which they are measured, which is similar to what is known for biological rates. This correlation explains why the pace of cultural evolution appears faster when measured over recent time periods, where time intervals are often shorter. Controlling for the correlation between rates and time intervals, I show that (1) cultural evolution is faster than biological evolution; (2) this effect holds true even when the generation time of species is controlled for; and (3) culture allows us to evolve over short time scales, which are normally accessible only to short-lived species, while at the same time allowing for us to enjoy the benefits of having a long life history. PMID:23024804

  13. Heart rhythm during permanent cardiac pacing.

    PubMed Central

    Edhag, O; Rosenqvist, M

    1979-01-01

    Heart rhythm was analysed with regard to spontaneous or pacemaker-induced heart activity, in a consecutive series of 282 patients paced for at least 1 year. The mean duration of pacing was 59 (13 to 180) months. The mean age of the patients was 76 (39 to 93) years. Spontaneous heart activity at all routine examinations was found in 33 (12%) of the patients. Pacemaker-induced rhythm only was recorded in 42 per cent of the patients whereas the remaining 46 per cent had varying electrocardiographic patterns. Of the patients with spontaneous rhythm at each visit, 10 had had complete heart block before pacing. Regular sinus activity was recorded at every routine examination in 74 per cent of the patients paced for reasons other than the sick sinus syndrome. This indicated that a substantial number of paced patients might be candidates for atrial triggered pacing. Patients treated with digitalis more often had asystole at the time of replacement of the pacemaker (32%) than those not so treated (19). This suggests an increased risk of sudden death in paced patients on digitalis if the pacemaker fails. PMID:486279

  14. 42 CFR 460.180 - Medicare payment to PACE organizations.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... SERVICES (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) Payment § 460.180 Medicare payment to PACE organizations. (a) Principle...

  15. 42 CFR 460.170 - Reinstatement in PACE.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) Participant Enrollment and Disenrollment § 460.170 Reinstatement in PACE. (a) A...

  16. 42 CFR 460.180 - Medicare payment to PACE organizations.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... SERVICES (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) Payment § 460.180 Medicare payment to PACE organizations. (a) Principle...

  17. 42 CFR 460.122 - PACE organization's appeals process.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... SERVICES (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) Participant Rights § 460.122 PACE organization's appeals process. For...

  18. 42 CFR 460.122 - PACE organization's appeals process.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... SERVICES (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) Participant Rights § 460.122 PACE organization's appeals process. For...

  19. 42 CFR 460.122 - PACE organization's appeals process.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... SERVICES (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) Participant Rights § 460.122 PACE organization's appeals process. For...

  20. 42 CFR 460.170 - Reinstatement in PACE.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) Participant Enrollment and Disenrollment § 460.170 Reinstatement in PACE. (a) A...

  1. 42 CFR 460.170 - Reinstatement in PACE.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) Participant Enrollment and Disenrollment § 460.170 Reinstatement in PACE. (a) A...

  2. 42 CFR 460.122 - PACE organization's appeals process.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... SERVICES (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) Participant Rights § 460.122 PACE organization's appeals process. For...

  3. 42 CFR 460.180 - Medicare payment to PACE organizations.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... SERVICES (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) Payment § 460.180 Medicare payment to PACE organizations. (a) Principle...

  4. 42 CFR 460.170 - Reinstatement in PACE.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) Participant Enrollment and Disenrollment § 460.170 Reinstatement in PACE. (a) A...

  5. Ventricular defibrillation combining DC electrical field and electrical pacing: an optical mapping study

    NASA Astrophysics Data System (ADS)

    Musunuri, Sai Shruthi; Tang, Liang; Joung, Boyoung; Berbari, Edward J.; Lin, Shien-Fong

    2009-02-01

    Although high voltage direct current (DC) shock is a standard technique to terminate ventricular fibrillation (VF), it can cause severe pain and tissue damage. The exact effect of the DC electric field, which can depolarize the heart during VF is still unknown. We hypothesized that low-energy DC field in combination with pacing (pacing+DC) could terminate VF by affecting the ventricular propagation pattern. In six Langendorff-perfused isolated rabbit hearts with the ablated sinoatrial (SA) node, the DC field was delivered to the left ventricle (cathode) and right ventricle (anode). We designed a timed protocol using LabVIEW programming that delivers pacing, DC and pacing+DC stimuli for two seconds time intervals each. The pacing pulse (with varying pacing cycle length: 300ms-30ms) was delivered to the apex. Transmembrane voltage was recorded with optical mapping technique for 16 seconds at a sampling rate of 2ms/frame. We crushed the sinoatrial node to reduce the heart rate. The baseline activation appeared to have endocardial origins with a mean escape ventricular rate of 60 +/- 5bpm at baseline. The DC field (30mA-60mA) alone increased the mean heart rate to 120+/-5bpm. Although DC alone terminated VF in a few cases, the rate of termination was very low (6.2%). However, when pacing+DC was applied, it was possible to terminate VF in 34 of 130 episodes in six rabbits. The rate of successful defibrillation of VF with pacing+DC was significantly higher than that with DC alone (20% vs 6.2%, p<0.01). Pacing alone never terminated the VF. In conclusion, DC field may affect the conduction velocity in normal condition. Pacing+DC intervention could lead to regularization of VF propagation and eventually to termination. Further improvement of this approach may offer a higher success rate of defibrillation with lower energy requirements.

  6. Self-Paced Instruction--New Directions

    ERIC Educational Resources Information Center

    Blum, Lester

    1976-01-01

    An argument that teaching introductory economic analysis can be made more effective with self-paced instruction using appropriately designed materials such as films, cassettes, and programmed learning units. (Author/AV)

  7. Conservation law for self-paced movements.

    PubMed

    Huh, Dongsung; Sejnowski, Terrence J

    2016-08-01

    Optimal control models of biological movements introduce external task factors to specify the pace of movements. Here, we present the dual to the principle of optimality based on a conserved quantity, called "drive," that represents the influence of internal motivation level on movement pace. Optimal control and drive conservation provide equivalent descriptions for the regularities observed within individual movements. For regularities across movements, drive conservation predicts a previously unidentified scaling law between the overall size and speed of various self-paced hand movements in the absence of any external tasks, which we confirmed with psychophysical experiments. Drive can be interpreted as a high-level control variable that sets the overall pace of movements and may be represented in the brain as the tonic levels of neuromodulators that control the level of internal motivation, thus providing insights into how internal states affect biological motor control. PMID:27418602

  8. Optogenetic pacing in Drosophila melanogaster (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Alex, Aneesh; Li, Airong; Men, Jing; Jerwick, Jason; Tanzi, Rudolph E.; Zhou, Chao

    2016-03-01

    A non-invasive, contact-less cardiac pacing technology can be a powerful tool in basic cardiac research and in clinics. Currently, electrical pacing is the gold standard for cardiac pacing. Although highly effective in controlling the cardiac function, the invasive nature, non-specificity to cardiac tissues and possible tissue damage limits its capabilities. Optical pacing of heart is a promising alternative, which is non-invasive and more specific, has high spatial and temporal precision, and avoids shortcomings in electrical stimulation. Optical coherence tomography has been proved to be an effective technique in non-invasive imaging in vivo with ultrahigh resolution and imaging speed. In the last several years, non-invasive specific optical pacing in animal hearts has been reported in quail, zebrafish, and rabbit models. However, Drosophila Melanogaster, which is a significant model with orthologs of 75% of human disease genes, has rarely been studied concerning their optical pacing in heart. Here, we combined optogenetic control of Drosophila heartbeat with optical coherence microscopy (OCM) technique for the first time. The light-gated cation channel, channelrhodopsin-2 (ChR2) was specifically expressed by transgene as a pacemaker in drosophila heart. By stimulating the pacemaker with 472 nm pulsed laser light at different frequencies, we achieved non-invasive and more specific optical control of the Drosophila heart rhythm, which demonstrates the wide potential of optical pacing for studying cardiac dynamics and development. Imaging capability of our customized OCM system was also involved to observe the pacing effect visually. No tissue damage was found after long exposure to laser pulses, which proved the safety of optogenetic control of Drosophila heart.

  9. An Undergraduate Intern Program at PACES

    NASA Technical Reports Server (NTRS)

    Starks, Scott A.

    1997-01-01

    The University of Texas at El Paso (UTEP) established the Pan American Center for Earth and Environmental Studies (PACES) in 1995 to conduct basic and applied research that contributes to NASA's Mission to Planet Earth. Specifically, PACES provides a repository of remote sensing and other information that supports investigations into an improved understanding of geological, ecological and environmental processes occurring in the southwestern United States and Northern Mexico. Approximately 85% of UTEP's students come from El Paso County, a fast growing urban region representative of many large cities in the Southwest that have, or will soon have, a majority of their population composed of groups currently underrepresented in the scientific and technical workforce. UTEP's student population has an ethnic distribution (63% Hispanic, 32% Anglo, 3% African American, 1.5 % Asian American, and less than 1% Native American) that closely matches the demographics of the region it serves. Thus, UTEP has a mission to serve a multicultural population where minority students comprise the majority. Most Hispanic students at UTEP are primarily of Mexican origin. A large number are first or second-generation U.S. citizens. Characteristics that unite Hispanic students, in particular those of Mexican-origin, are a strong sense of family loyalty and a belief that all family members are responsible for contributing to the economic stability and well-being of the family. Most of their families are larger in number than the national average, and a variety of generations live together or share considerable resources. Thus, many young people feel an obligation and a desire to go to work at a young age and to continue working while in college, thereby assisting their parents and other family members. Older siblings understand that they have responsibilities to do household chores, to aid their younger siblings economically, and to assist elderly family members. This "work ethic" within the

  10. COUPLING

    DOEpatents

    Frisch, E.; Johnson, C.G.

    1962-05-15

    A detachable coupling arrangement is described which provides for varying the length of the handle of a tool used in relatively narrow channels. The arrangement consists of mating the key and keyhole formations in the cooperating handle sections. (AEC)

  11. High-resolution entrainment mapping of gastric pacing: a new analytical tool.

    PubMed

    O'Grady, Gregory; Du, Peng; Lammers, Wim J E P; Egbuji, John U; Mithraratne, Pulasthi; Chen, Jiande D Z; Cheng, Leo K; Windsor, John A; Pullan, Andrew J

    2010-02-01

    Gastric pacing has been investigated as a potential treatment for gastroparesis. New pacing protocols are required to improve symptom and motility outcomes; however, research progress has been constrained by a limited understanding of the effects of electrical stimulation on slow-wave activity. This study introduces high-resolution (HR) "entrainment mapping" for the analysis of gastric pacing and presents four demonstrations. Gastric pacing was initiated in a porcine model (typical amplitude 4 mA, pulse width 400 ms, period 17 s). Entrainment mapping was performed using flexible multielectrode arrays (paced propagation was found to be anisotropic (longitudinal 2.6 +/- 1.7 vs. circumferential 4.5 +/- 0.6 mm/s; P < 0.001). In the third demonstration, a dysrhythmic episode that occurred during pacing was mapped in HR, revealing an ectopic slow-wave focus and uncoupled propagations. In the fourth demonstration, differences were observed between paced and native slow-wave amplitudes (0.24 +/- 0.08 vs. 0.38 +/- 0.14 mV; P < 0.001), velocities (6.2 +/- 2.8 vs. 11.5 +/- 4.7 mm/s; P < 0.001), and activated areas (20.6 +/- 1.9 vs. 32.8 +/- 2.6 cm(2); P < 0.001). Entrainment mapping enables an accurate quantification of the effects of gastric pacing on slow-wave activity, offering an improved method to assess whether pacing protocols are likely to achieve physiologically and clinically useful outcomes. PMID:19926815

  12. Mechanical Coupling Error Suppression Technology for an Improved Decoupled Dual-Mass Micro-Gyroscope.

    PubMed

    Yang, Bo; Wang, Xingjun; Deng, Yunpeng; Hu, Di

    2016-01-01

    This paper presents technology for the suppression of the mechanical coupling errors for an improved decoupled dual-mass micro-gyroscope (DDMG). The improved micro-gyroscope structure decreases the moment arm of the drive decoupled torque, which benefits the suppression of the non-ideal decoupled error. Quadrature correction electrodes are added to eliminate the residual quadrature error. The structure principle and the quadrature error suppression means of the DDMG are described in detail. ANSYS software is used to simulate the micro-gyroscope structure to verify the mechanical coupling error suppression effect. Compared with the former structure, simulation results demonstrate that the rotational displacements of the sense frame in the improved structure are substantially suppressed in the drive mode. The improved DDMG structure chip is fabricated by the deep dry silicon on glass (DDSOG) process. The feedback control circuits with quadrature control loops are designed to suppress the residual mechanical coupling error. Finally, the system performance of the DDMG prototype is tested. Compared with the former DDMG, the quadrature error in the improved dual-mass micro-gyroscope is decreased 9.66-fold, and the offset error is decreased 6.36-fold. Compared with the open loop sense, the feedback control circuits with quadrature control loop decrease the bias drift by 20.59-fold and the scale factor non-linearity by 2.81-fold in the ±400°/s range. PMID:27070616

  13. Mechanical Coupling Error Suppression Technology for an Improved Decoupled Dual-Mass Micro-Gyroscope

    PubMed Central

    Yang, Bo; Wang, Xingjun; Deng, Yunpeng; Hu, Di

    2016-01-01

    This paper presents technology for the suppression of the mechanical coupling errors for an improved decoupled dual-mass micro-gyroscope (DDMG). The improved micro-gyroscope structure decreases the moment arm of the drive decoupled torque, which benefits the suppression of the non-ideal decoupled error. Quadrature correction electrodes are added to eliminate the residual quadrature error. The structure principle and the quadrature error suppression means of the DDMG are described in detail. ANSYS software is used to simulate the micro-gyroscope structure to verify the mechanical coupling error suppression effect. Compared with the former structure, simulation results demonstrate that the rotational displacements of the sense frame in the improved structure are substantially suppressed in the drive mode. The improved DDMG structure chip is fabricated by the deep dry silicon on glass (DDSOG) process. The feedback control circuits with quadrature control loops are designed to suppress the residual mechanical coupling error. Finally, the system performance of the DDMG prototype is tested. Compared with the former DDMG, the quadrature error in the improved dual-mass micro-gyroscope is decreased 9.66-fold, and the offset error is decreased 6.36-fold. Compared with the open loop sense, the feedback control circuits with quadrature control loop decrease the bias drift by 20.59-fold and the scale factor non-linearity by 2.81-fold in the ±400°/s range. PMID:27070616

  14. Improved control of the betatron coupling in the Large Hadron Collider

    NASA Astrophysics Data System (ADS)

    Persson, T.; Tomás, R.

    2014-05-01

    The control of the betatron coupling is of importance for safe beam operation in the LHC. In this article we show recent advancements in methods and algorithms to measure and correct coupling. The benefit of using a more precise formula relating the resonance driving term f1001 to the ΔQmin is presented. The quality of the coupling measurements is increased, with about a factor 3, by selecting beam position monitor (BPM) pairs with phase advances close to π/2 and through data cleaning using singular value decomposition with an optimal number of singular values. These improvements are beneficial for the implemented automatic coupling correction, which is based on injection oscillations, presented in the article. Furthermore, a proposed coupling feedback for the LHC is presented. The system will rely on the measurements from BPMs equipped with a new type of high resolution electronics, diode orbit and oscillation, which will be operational when the LHC restarts in 2015. The feedback will combine the coupling measurements from the available BPMs in order to calculate the best correction.

  15. The pace of vocabulary growth helps predict later vocabulary skill

    PubMed Central

    Rowe, Meredith L.; Raudenbush, Stephen W.; Goldin-Meadow, Susan

    2011-01-01

    Children vary widely in the rate at which they acquire words—some start slow and speed up, others start fast and continue at a steady pace. Do early developmental variations of this sort help predict vocabulary skill just prior to kindergarten entry? This longitudinal study starts by examining important predictors (SES, parent input, child gesture) of vocabulary growth between 14 and 46 months (n=62), and then uses growth estimates to predict children's vocabulary at 54 months. Velocity and acceleration in vocabulary development at 30 months predicted later vocabulary, particularly for children from low socioeconomic backgrounds. Understanding the pace of early vocabulary growth thus improves our ability to predict school readiness, and may help identify children at risk for starting behind. PMID:22235920

  16. Temporary leadless pacing in a patient with severe device infection.

    PubMed

    Kypta, Alexander; Blessberger, Hermann; Lichtenauer, Michael; Steinwender, Clemens

    2016-01-01

    A 64-year-old patient underwent implantation of a transcatheter pacing systems (TPS) for severe lead endocarditis. The patient experienced fever after a dental procedure. On the transoesophageal echocardiogram (TEE), vegetations were attached to the leads. Because the patient was pacemaker dependent, a temporary pacing lead had to be placed. After removal, however, he did not improve. A second TEE showed new vegetations. Ventricular fibrillation occurred spontaneously; so isoprenalin had to be stopped and a new lead was implanted. Vegetations appeared soon after the new temporary lead was placed. We used a TPS as a bridging device, followed by implantation of a resynchronisation system, and explantation of the TPS. After the Micra TPS was implanted, the patient recovered noticeably. All inflammation parameters were negative and an additional (18)F-fluorodeoxyglucose-positron emission tomography/CT imaging also proved to be negative. So a CRT-D device was then implanted, and the TCP was removed. PMID:27190123

  17. Improving the security of optoelectronic delayed feedback system by parameter modulation and system coupling

    NASA Astrophysics Data System (ADS)

    Liu, Lingfeng; Miao, Suoxia; Cheng, Mengfan; Gao, Xiaojing

    2016-02-01

    A coupled system with varying parameters is proposed to improve the security of optoelectronic delayed feedback system. This system is coupled by two parameter-varied optoelectronic delayed feedback systems with chaotic modulation. Dynamics performance results show that this system has a higher complexity compared to the original one. Furthermore, this system can conceal the time delay effectively against the autocorrelation function and delayed mutual information method and can increase the dimension space of secure parameters to resist brute-force attack by introducing the digital chaotic systems.

  18. The roles of pacing interval and pacing strength in ventricular fibrillation induced by rapid pacing with 1 : 1 capture

    PubMed Central

    Zhao, Dongdong; Liu, Ban; Wei, Yidong; Tang, Kai; Yu, Xuejing

    2015-01-01

    Introduction The roles of pacing interval (PI) and pacing strength (PS) in ventricular fibrillation (VF) induced by rapid pacing with 1 : 1 capture remain unclear. Material and methods Epicardial unipolar electrograms (UEs) were simultaneously recorded using contact mapping in 11 swine. Activation-recovery interval (ARI) restitution was constructed at 4 sites, i.e. the apex and base of the left and right ventricles, respectively. A steady state pacing (SSP) protocol was performed to induce VF. The longest PI and the lowest PS for inducing VF were recorded. Statistical correlation analysis was performed to determine the relationship between local ARI restitution properties and PI and PS for VF induction. Results Forty restitution curves were constructed from 11 SSP procedures. The maximal slope (Smax) of the ARI restitution curve of the right ventricular apex was positively correlated with the PI for VF induction (r = 0.761, p < 0.05). Spatial dispersions of ARI and Smax were negatively correlated with the PS for VF induction (r = –0.626 and r = –0.722, respectively, both p < 0.05). Conclusions Ventricular fibrillation can be induced by rapid ventricular pacing with 1 : 1 capture. The PI for VF induction was related to the Smax of the ARI restitution curve of the right ventricular apex, while PS for VF induction was associated with the spatial dispersions of ARI and its restitution property. PMID:26528357

  19. 42 CFR 460.180 - Medicare payment to PACE organizations.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... payment. Under a PACE program agreement, CMS makes a prospective monthly payment to the PACE organization... Medicare Advantage organization. (b) Determination of rate. (1) The PACE program agreement specifies the methodology used to calculate the monthly capitation amount applicable to a PACE organization. (2) Except...

  20. PACE4: a subtilisin-like endoprotease with unique properties.

    PubMed Central

    Mains, R E; Berard, C A; Denault, J B; Zhou, A; Johnson, R C; Leduc, R

    1997-01-01

    PACE4 is one of the neuroendocrine-specific mammalian subtilisin-related endoproteases believed to function in the secretory pathway. The biosynthesis and secretion of PACE4 have been studied using transfected neuroendocrine and fibroblast cell lines. as well as primary pituitary cultures. ProPACE4 (approx. 106 kDa) is cleaved intracellularly before secretion of PACE4 (approx. 97 kDa); the N-terminal propeptide cleavage is accelerated in a truncated form of PACE4 lacking the Cys-rich C-terminal region (PACE4s). Neither PACE4 nor PACE4s is stored in regulated neuroendocrine secretory granules, whereas pro-opiomelanocortin-derived peptides and prohormone convertase I enter the regulated secretory pathway efficiently. The relatively slow cleavage of the proregion of proPACE4 in primary anterior pituitary cells, followed by rapid secretion of PACE4, is similar to the results for proPACE4 in transfected cell lines. The enzyme activity of PACE4 is distinct from furin and prohormone convertases, both in the marked sensitivity of PACE4 to inhibition by leupeptin and the relative insensitivity of PACE4 to inhibition by Ca2+ chelators and dithiothreitol; PACE4 is not inhibited by the alpha1-antitrypsin Portland variant that is very potent at inhibiting furin. The unique biosynthetic and enzymic patterns seen for PACE4 suggest a role for this neuroendocrine-specific subtilisin-like endoprotease outside the pathway for peptide biosynthesis. PMID:9032441

  1. 42 CFR 460.180 - Medicare payment to PACE organizations.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... payment. Under a PACE program agreement, CMS makes a prospective monthly payment to the PACE organization... Medicare Advantage organization. (b) Determination of rate. (1) The PACE program agreement specifies the methodology used to calculate the monthly capitation amount applicable to a PACE organization. (2) Except...

  2. Neurophysiological determinants of theoretical concepts and mechanisms involved in pacing.

    PubMed

    Roelands, Bart; de Koning, Jos; Foster, Carl; Hettinga, Floor; Meeusen, Romain

    2013-05-01

    improve performance. The distribution of the power output reveals that after dopamine reuptake inhibition, subjects are able to maintain a higher power output compared with placebo. Manipulations of serotonin and, especially, noradrenaline, have the opposite effect and force subjects to decrease power output early in the time trial. Interestingly, after manipulation of brain serotonin, subjects are often unable to perform an end sprint, indicating an absence of a reserve capacity or motivation to increase power output. Taken together, it appears that many factors, such as ambient conditions and manipulation of brain neurotransmitters, have the potential to influence power output during exercise, and might thus be involved as regulatory mechanisms in the complex skill of pacing. PMID:23456493

  3. Improved Helicopter Rotor Performance Prediction through Loose and Tight CFD/CSD Coupling

    NASA Astrophysics Data System (ADS)

    Ickes, Jacob C.

    Helicopters and other Vertical Take-Off or Landing (VTOL) vehicles exhibit an interesting combination of structural dynamic and aerodynamic phenomena which together drive the rotor performance. The combination of factors involved make simulating the rotor a challenging and multidisciplinary effort, and one which is still an active area of interest in the industry because of the money and time it could save during design. Modern tools allow the prediction of rotorcraft physics from first principles. Analysis of the rotor system with this level of accuracy provides the understanding necessary to improve its performance. There has historically been a divide between the comprehensive codes which perform aeroelastic rotor simulations using simplified aerodynamic models, and the very computationally intensive Navier-Stokes Computational Fluid Dynamics (CFD) solvers. As computer resources become more available, efforts have been made to replace the simplified aerodynamics of the comprehensive codes with the more accurate results from a CFD code. The objective of this work is to perform aeroelastic rotorcraft analysis using first-principles simulations for both fluids and structural predictions using tools available at the University of Toledo. Two separate codes are coupled together in both loose coupling (data exchange on a periodic interval) and tight coupling (data exchange each time step) schemes. To allow the coupling to be carried out in a reliable and efficient way, a Fluid-Structure Interaction code was developed which automatically performs primary functions of loose and tight coupling procedures. Flow phenomena such as transonics, dynamic stall, locally reversed flow on a blade, and Blade-Vortex Interaction (BVI) were simulated in this work. Results of the analysis show aerodynamic load improvement due to the inclusion of the CFD-based airloads in the structural dynamics analysis of the Computational Structural Dynamics (CSD) code. Improvements came in the form

  4. A Simulation Study of Paced TCP

    NASA Technical Reports Server (NTRS)

    Kulik, Joanna; Coulter, Robert; Rockwell, Dennis; Partridge, Craig

    2000-01-01

    In this paper, we study the performance of paced TCP, a modified version of TCP designed especially for high delay- bandwidth networks. In typical networks, TCP optimizes its send-rate by transmitting increasingly large bursts, or windows, of packets, one burst per round-trip time, until it reaches a maximum window-size, which corresponds to the full capacity of the network. In a network with a high delay-bandwidth product, however, Transmission Control Protocol's (TCPs) maximum window-size may be larger than the queue size of the intermediate routers, and routers will begin to drop packets as soon as the windows become too large for the router queues. The TCP sender then concludes that the bottleneck capacity of the network has been reached, and it limits its send-rate accordingly. Partridge proposed paced TCP as a means of solving the problem of queueing bottlenecks. A sender using paced TCP would release packets in multiple, small bursts during a round-trip time in which ordinary TCP would release a single, large burst of packets. This approach allows the sender to increase its send-rate to the maximum window size without encountering queueing bottlenecks. This paper describes the performance of paced TCP in a simulated network and discusses implementation details that can affect the performance of paced TCP.

  5. Carrier arraying with coupled phase-locked loops for tracking improvement

    NASA Technical Reports Server (NTRS)

    Divsalar, D.; Yuen, J. H.

    1982-01-01

    This paper considers a system that couples several phase-locked loops (PLL's) to improve carrier tracking performance. The system coherently combines the received carrier signals at geographically separated ground antennas to increase the total effective aperture. It automatically aligns the received carrier's phases to enhance received carrier signal-to-noise ratio. The tracking performance of this system is being assessed in terms of rms phase jitter.

  6. Improvements and applications of COBRA-TF for stand-alone and coupled LWR safety analyses

    SciTech Connect

    Avramova, M.; Cuervo, D.

    2006-07-01

    The advanced thermal-hydraulic subchannel code COBRA-TF has been recently improved and applied for stand-alone and coupled LWR core calculations at the Pennsylvania State Univ. in cooperation with AREVA NP GmbH (Germany)) and the Technical Univ. of Madrid. To enable COBRA-TF for academic and industrial applications including safety margins evaluations and LWR core design analyses, the code programming, numerics, and basic models were revised and substantially improved. The code has undergone through an extensive validation, verification, and qualification program. (authors)

  7. Pacing hazards in helicopter aeromedical transport.

    PubMed

    Sumchai, A; Sternbach, G; Eliastam, M; Liem, L B

    1988-05-01

    A 62-year-old man with third-degree atrioventricular block and hemodynamically unstable ventricular tachycardia had a cardiac arrest during helicopter transport to a specialized cardiac care unit. Before transport, his ventricular tachycardia had been successfully terminated by a rapid overdrive pacing technique. The failure of "burst suppression" and the absence of pacer spike artifact on the electrocardiographic monitor raise questions about the potential hazards of using various pacing techniques during helicopter transports. Most significantly, this case points to the possibility of interference by exogenous electromagnetic signals in the medical compartment of the helicopter. PMID:3370099

  8. Skin to skin interactions. Does the infant massage improve the couple functioning?

    PubMed Central

    Gnazzo, Antonio; Guerriero, Viviana; Di Folco, Simona; Zavattini, Giulio C.; de Campora, Gaia

    2015-01-01

    Transition to parenthood is a critical stage of life due to several changes the couple has to handle. A large body of studies described how transition to parenthood can be linked to the onset of depressive symptoms, as well as the perception of a low social support, and an increased stress, representing a risk for the early mother–baby relationship. Infant massage (IM) emerged as a helpful tool to improve maternal skills in interacting with the baby, and leading toward a decreasing of post-partum symptoms. However, a growing body of literature highlights that men also may experience post-partum diseases, representing an additional risk for the development of the baby. To date, no study observed the impact of the IM on both partners. The aim of the current qualitative research is to observe the impact of the IM on a single couple of parents at childbirth. Pre (Time 1) and post-intervention (Time 3) procedure has been established to observe the changes occurring over the time in the couple. In particular, each member of the couple filled out the EPDS, the BDI-II, the MSPSS, and the PSI-SF both at Time 1 and at Time 3. The treatment (Time 2) was represented by the IM training, and lasted 4 weeks. Findings revealed a decrease in depressive symptoms in both partners, as well as an improvement of their perception of stress related to parental role. No changes has been detected with respect to the perception of social support. The IM seems to be a helpful approach to prevent the establishment of pathological conditions in new parents. Although no direct measures on the child were used, the current qualitative data seem to suggest that the IM may represent a valuable tool to prevent the onset of early negative outcomes of the baby. Further investigations and empirical data are needed to improve the knowledge in this field. PMID:26441813

  9. Skin to skin interactions. Does the infant massage improve the couple functioning?

    PubMed

    Gnazzo, Antonio; Guerriero, Viviana; Di Folco, Simona; Zavattini, Giulio C; de Campora, Gaia

    2015-01-01

    Transition to parenthood is a critical stage of life due to several changes the couple has to handle. A large body of studies described how transition to parenthood can be linked to the onset of depressive symptoms, as well as the perception of a low social support, and an increased stress, representing a risk for the early mother-baby relationship. Infant massage (IM) emerged as a helpful tool to improve maternal skills in interacting with the baby, and leading toward a decreasing of post-partum symptoms. However, a growing body of literature highlights that men also may experience post-partum diseases, representing an additional risk for the development of the baby. To date, no study observed the impact of the IM on both partners. The aim of the current qualitative research is to observe the impact of the IM on a single couple of parents at childbirth. Pre (Time 1) and post-intervention (Time 3) procedure has been established to observe the changes occurring over the time in the couple. In particular, each member of the couple filled out the EPDS, the BDI-II, the MSPSS, and the PSI-SF both at Time 1 and at Time 3. The treatment (Time 2) was represented by the IM training, and lasted 4 weeks. Findings revealed a decrease in depressive symptoms in both partners, as well as an improvement of their perception of stress related to parental role. No changes has been detected with respect to the perception of social support. The IM seems to be a helpful approach to prevent the establishment of pathological conditions in new parents. Although no direct measures on the child were used, the current qualitative data seem to suggest that the IM may represent a valuable tool to prevent the onset of early negative outcomes of the baby. Further investigations and empirical data are needed to improve the knowledge in this field. PMID:26441813

  10. Evaluation of an 18-couple module composed of improved performance SiGe unicouples

    SciTech Connect

    Kelly, C.E.; Klee, P.M.; Nakahara, J.F.; Hartman, R.F.

    1995-12-31

    Radioisotope Thermoelectric Generators (RTGs) have played a major role in providing spacecraft electrical power for interplanetary exploration. Silicon Germanium alloys are the thermoelectric material employed in RTGs. Over the past several years a number of investigations have reported improvements in the figure of merit of these alloys. These improvements are attractive to mission planners because they result in enhanced RTG specific power (watts/lb) and improved efficiency which leads to lower fuel costs. This paper describes the fabrication and testing of an 18-couple module device utilizing unicouples with improved SiGe alloys. The unicouples were fabricated using materials with over a 10% improvement in the 573 to 1,273 K integrated average figure-of-merit over Cassini materials. The p-type material was fabricated by the standard vacuum casting and hot pressing method while the n-type material containing GaP was fabricated by a new method of mechanical alloying and hot isostatic pressing. The unicouples were fabricated in a similar fashion to standard unicouples except that the thermoelectric materials were bonded to the SiMo hot shoe in two thermal cycles due to the disparity of the melting points. A sufficient quantity of unicouples was fabricated to assemble an 18-couple module to evaluate the thermoelectric performance of the improved SiGe materials. The module was brought up to operating temperature following the same heatup rate as previous modules. The module was stabilized at a hot shoe temperature of 1,308 K. Initial performance was compared to the established SiGe database and found to show no improvement thermally or electrically.

  11. Improved ENSO forecasts by assimilating sea surface temperature observations into an intermediate coupled model

    NASA Astrophysics Data System (ADS)

    Zheng, F.; Zhu, J.; Zhang, R. H.; Zhou, G. Q.

    2006-07-01

    A simple method for initializing intermediate coupled models (ICMs) using only sea surface temperature (SST) anomaly data is comprehensively tested in two sets of hindcasts with a new ICM. In the initialization scheme, both the magnitude of the nudging parameter and the duration of the assimilation are considered, and initial conditions for both atmosphere and ocean are generated by running the coupled model with SST anomalies nudged to the observations. A comparison with the observations indicates that the scheme can generate realistic thermal fields and surface dynamic fields in the equatorial Pacific through hindcast experiments. An ideal experiment is performed to get the optimal nudging parameters which include the nudging intensity and nudging time length. Twelve-month-long hindcast experiments are performed with the model over the period 1984-2003 and the period 1997-2003. Compared with the original prediction results, the model prediction skills are significantly improved by the nudging method especially beyond a 6-month lead time during the two different periods. Potential problems and further improvements are discussed regarding the new coupled assimilation system.

  12. A study on improvement of discharge characteristic by using a transformer in a capacitively coupled plasma

    SciTech Connect

    Kim, Young-Cheol; Kim, Hyun-Jun; Lee, Hyo-Chang; Chung, Chin-Wook

    2015-12-15

    In a plasma discharge system, the power loss at powered line, matching network, and other transmission line can affect the discharge characteristics such as the power transfer efficiency, voltage and current at powered electrode, and plasma density. In this paper, we propose a method to reduce power loss by using a step down transformer mounted between the matching network and the powered electrode in a capacitively coupled argon plasma. This step down transformer decreases the power loss by reducing the current flowing through the matching network and transmission line. As a result, the power transfer efficiency was increased about 5%–10% by using a step down transformer. However, the plasma density was dramatically increased compared to no transformer. This can be understood by the increase in ohmic heating and the decrease in dc-self bias. By simply mounting a transformer, improvement of discharge efficiency can be achieved in capacitively coupled plasmas.

  13. Developmental Math, Flipped and Self-Paced

    ERIC Educational Resources Information Center

    Weng, Pangyen

    2015-01-01

    This article describes a developmental math course design that uses flipped instruction and self-paced learning. The design was created and taught at Metropolitan State University, where most students are returning adult students with little preparation in mathematics. The author argues that this design suits the students well: the learning…

  14. Internship: A Pacing Guide for Student Teachers.

    ERIC Educational Resources Information Center

    Berrones, Elma; And Others

    This pacing guide is a detailed outline that provides trainees with a building-block approach to the aquisition of teaching skills. In addition, it provides clarity to the roles and responsibilities of the intern, the cooperating teacher, and the supervisor, and coordinates the classroom experience for the third semester of a four-semester…

  15. Program for Alternative Careers in Education (PACE).

    ERIC Educational Resources Information Center

    Flicker, Bernard

    The overall objective of the Program for Alternative Careers in Education (PACE) is to develop an alternative model of teacher preparation that prepares individuals to function as educators in the widest possible variety of educational institutions including public and private human service institutions, social welfare agencies, communication…

  16. An Integrated Preprofessional Individually Paced Instruction Curriculum.

    ERIC Educational Resources Information Center

    McCollom, Kenneth A.; Kurtz, Edwin B.

    The individually-paced instruction program carried out by the engineering faculty at Oklahoma State University is described in this article to illustrate its goals, principles, characteristics, developments, and present status. The instructional model is discussed in connection with behavioral objectives, criteria for performance, and student…

  17. Self-Paced Graphics with Track Options.

    ERIC Educational Resources Information Center

    Hilliard, Garland K.

    An engineering graphics course offered at North Carolina State University for freshman engineering students is described. The course is divided into 14 units and the students are allowed to proceed at their own pace. The first 11 units comprise the required core; the remaining 3 units may be chosen from other areas such as computer graphics,…

  18. Self-Paced Physics, Instructor Manual.

    ERIC Educational Resources Information Center

    New York Inst. of Tech., Old Westbury.

    As a part of the U. S. Naval Academy Self-Paced Physics Course materials, orientation is presented in this manual to assist an instructor in developing his individual class policies. Descriptions are given of objectives, class atmosphere, student progress, counseling activities, and remedial work. Under the heading of the management sequence,…

  19. Improving the implementation of tailored expectant management in subfertile couples: protocol for a cluster randomized trial

    PubMed Central

    2013-01-01

    Background Prognostic models in reproductive medicine can help to identify subfertile couples who would benefit from fertility treatment. Expectant management in couples with a good chance of natural conception, i.e., tailored expectant management (TEM), prevents unnecessary treatment and is therefore recommended in international fertility guidelines. However, current implementation is not optimal, leaving room for improvement. Based on barriers and facilitators for TEM that were recently identified among professionals and subfertile couples, we have developed a multifaceted implementation strategy. The goal of this study is to assess the effects of this implementation strategy on the guideline adherence on TEM. Methods/design In a cluster randomized trial, 25 clinics and their allied practitioners units will be randomized between the multifaceted implementation strategy and care as usual. Randomization will be stratified for in vitro fertilization (IVF) facilities (full licensed, intermediate/no IVF facilities). The effect of the implementation strategy, i.e., the percentage guideline adherence on TEM, will be evaluated by pre- and post-randomization data collection. Furthermore, there will be a process and cost evaluation of the strategy. The implementation strategy will focus on subfertile couples and their care providers i.e., general practitioners (GPs), fertility doctors, and gynecologists. The implementation strategy addresses three levels: patient level: education materials in the form of a patient information leaflet and a website; professional level: audit and feedback, educational outreach visit, communication training, and access to a digital version of the prognostic model of Hunault on a website; organizational level: providing a protocol based on the guideline. The primary outcome will be the percentage guideline adherence on TEM. Additional outcome measures will be treatment-, patient-, and process-related outcome measures. Discussion This study

  20. High performance patch antenna using circular split ring resonators and thin wires employing electromagnetic coupling improvement

    NASA Astrophysics Data System (ADS)

    Abdelrehim, Adel A. A.; Ghafouri-Shiraz, H.

    2016-09-01

    In this paper, three dimensional periodic structure composed of circular split ring resonators and thin wires is used to improve the performance of a microstrip patch antenna. The three dimensional periodic structure is placed at the top of the patch within a specific separation distance to construct the proposed antenna. The radiated electromagnetic waves intensity of the proposed antenna is improved compared with the conventional patch antenna due to the electric and magnetic coupling enhancements. These enhancements occur between the patch and the periodic structure resonators and between the different resonator pairs of the periodic structure. As a result, the electric and the magnetic fields at the top of the patch are improved, the radiated electromagnetic beam size reduces which results in a highly focused beam and hence the antenna directivity and gain are improved, while the beam are is reduced. The proposed antenna has been designed and simulated using CST microwave studio at 10 GHz. An infinite two dimensional periodicity unit cell of circular split ring resonator and thin wire is designed to resonate at a 10 GHz and simulated in CST software, the scattering parameters are extracted, the results showed that the infinite periodicity two dimensional structure has a pass band frequency response of good transmission and reflection characteristics around 10 GHz. The infinite periodicity of the two dimensional periodic structure is then truncated and multi layers of such truncated structure is used to construct a three dimensional periodic structure. A parametric analysis has been performed on the proposed antenna incorporated with the three dimensional periodic structure. The impacts of the separation distance between the patch and three dimensional periodic structures and the size of the three dimensional periodic structure on the radiation and impedance matching parameters of the proposed antenna are studied. For experimental verification, the proposed

  1. Towards improved capability and confidence in coupled atmospheric and wildland fire modeling

    NASA Astrophysics Data System (ADS)

    Sauer, Jeremy A.

    This dissertation work is aimed at improving the capability and confidence in a modernized and improved version of Los Alamos National Laboratory's coupled atmospheric and wild- land fire dynamics model, Higrad-Firetec. Higrad is the hydrodynamics component of this large eddy simulation model that solves the three dimensional, fully compressible Navier-Stokes equations, incorporating a dynamic eddy viscosity formulation through a two-scale turbulence closure scheme. Firetec is the vegetation, drag forcing, and combustion physics portion that is integrated with Higrad. The modern version of Higrad-Firetec incorporates multiple numerical methodologies and high performance computing aspects which combine to yield a unique tool capable of augmenting theoretical and observational investigations in order to better understand the multi-scale, multi-phase, and multi-physics, phenomena involved in coupled atmospheric and environmental dynamics. More specifically, the current work includes extended functionality and validation efforts targeting component processes in coupled atmospheric and wildland fire scenarios. Since observational data of sufficient quality and resolution to validate the fully coupled atmosphere-wildfire scenario simply does not exist, we instead seek to validate components of the full prohibitively convoluted process. This manuscript provides first, an introduction and background into the application space of Higrad-Firetec. Second we document the model formulation, solution procedure, and a simple scalar transport verification exercise. Third, we perform a validate model results against observational data for time averaged flow field metrics in and above four idealized forest canopies. Fourth, we carry out a validation effort for the non-buoyant jet in a crossflow scenario (to which an analogy can be made for atmosphere-wildfire interactions) comparing model results to laboratory data of both steady-in-time and unsteady-in-time metrics. Finally, an

  2. Toward a More Efficient Implementation of Antifibrillation Pacing

    PubMed Central

    Wilson, Dan; Moehlis, Jeff

    2016-01-01

    We devise a methodology to determine an optimal pattern of inputs to synchronize firing patterns of cardiac cells which only requires the ability to measure action potential durations in individual cells. In numerical bidomain simulations, the resulting synchronizing inputs are shown to terminate spiral waves with a higher probability than comparable inputs that do not synchronize the cells as strongly. These results suggest that designing stimuli which promote synchronization in cardiac tissue could improve the success rate of defibrillation, and point towards novel strategies for optimizing antifibrillation pacing. PMID:27391010

  3. Acute Resveratrol Consumption Improves Neurovascular Coupling Capacity in Adults with Type 2 Diabetes Mellitus

    PubMed Central

    Wong, Rachel H.X.; Raederstorff, Daniel; Howe, Peter R.C.

    2016-01-01

    Background: Poor cerebral perfusion may contribute to cognitive impairment in type 2 diabetes mellitus (T2DM). We conducted a randomized controlled trial to test the hypothesis that resveratrol can enhance cerebral vasodilator function and thereby alleviate the cognitive deficits in T2DM. We have already reported that acute resveratrol consumption improved cerebrovascular responsiveness (CVR) to hypercapnia. We now report the effects of resveratrol on neurovascular coupling capacity (CVR to cognitive stimuli), cognitive performance and correlations with plasma resveratrol concentrations. Methods: Thirty-six T2DM adults aged 40–80 years were randomized to consume single doses of resveratrol (0, 75, 150 and 300 mg) at weekly intervals. Transcranial Doppler ultrasound was used to monitor changes in blood flow velocity (BFV) during a cognitive test battery. The battery consisted of dual-tasking (finger tapping with both Trail Making task and Serial Subtraction 3 task) and a computerized multi-tasking test that required attending to four tasks simultaneously. CVR to cognitive tasks was calculated as the per cent increase in BFV from pre-test basal to peak mean blood flow velocity and also as the area under the curve for BFV. Results: Compared to placebo, 75 mg resveratrol significantly improved neurovascular coupling capacity, which correlated with plasma total resveratrol levels. Enhanced performance on the multi-tasking test battery was also evident following 75 mg and 300 mg of resveratrol. Conclusion: a single 75 mg dose of resveratrol was able to improve neurovascular coupling and cognitive performance in T2DM. Evaluation of benefits of chronic resveratrol supplementation is now warranted. PMID:27420093

  4. Evaluation of Long Term Effect of RV Apical Pacing on Global LV Function by Echocardiography

    PubMed Central

    Tilkar, Mahendra; Jain, Siddhant; Mondal, Subrata; Sarkar, Piyabi; Modi, Nitin

    2016-01-01

    Introduction We very often face pacemaker implanted patients during follow-up with shortness of breath and effort intolerance inspite of normal clinical parameters. Aim The aim of our study is to evaluate the cause of effort intolerance and probable cause of sub-clinical Congestive Cardiac Failure (CCF) in a case of long term Right Ventricular (RV) apical pacing on global Left Ventricular (LV) function non- invasively by echocardiography. Materials and Methods We studied 54 patients (Male 42, Female 12) of complete heart block (CHB) with RV apical pacing (40 VVI and 14 DCP). Mean duration of pacing was 58+4 months. All patients underwent 24 hours Holter monitoring to determine the percentage of ventricular pacing beats. 2-D Echocardiography was done to assess the regional wall motion of abnormality and global LV ejection fraction by modified Simpson’s rule. These methods were coupled with the Doppler derived Myocardial Performance Index (MPI), tissue Doppler imaging, and mechanical regional dyssynchrony with 3-D Echocardiography. Data were analysed from 54 RV- apical paced patients and compared with age and body surface area of 60 controlled subjects (Male 46, Female 14). Results Evaluation of LV function in 54 patients demonstrated regional wall motion abnormality and Doppler study revealed both LV systolic and diastolic dysfunction compare with control subjects (regional wall motion abnormality 80±6% vs 30±3% with p-value<0.0001) which is proportional to the percentage of ventricular pacing beats (mean paced beat 78%). Global LVEF 50±4% vs 60±2% (p-valve <0.0001) and MPI 0.46 ±0.12 v/s 0.36±0.09 (p-value <0.0001). Conclusion RV–apical pacing induces iatrogenic electrical dyssynchrony which leads to remodeling of LV and produces mechanical dyssynchrony which is responsible for LV dysfunction. Alternate site of RV pacing and/or biventricular pacing should be done to maintain biventricular electrical synchrony which will preserve the LV function. PMID

  5. Improved method of measuring pressure coupled response for composite solid propellants

    NASA Astrophysics Data System (ADS)

    Su, Wanxing; Wang, Ningfei; Li, Junwei; Zhao, Yandong; Yan, Mi

    2014-04-01

    Pressure coupled response is one of the main causes of combustion instability in the solid rocket motor. It is also a characteristic parameter for predicting the stability. The pressure coupled response function is usually measured by different methods to evaluate the performance of new propellant. Based on T-burner and "burning surface doubled and secondary attenuation", an improved method for measuring the pressure coupled response of composite propellant is introduced in this article. A computational fluid dynamics (CFD) study has also been conducted to validate the method and to understand the pressure oscillation phenomenon in T-burner. Three rounds of tests were carried out on the same batch of aluminized AP/HTPB composite solid propellant. The experimental results show that the sample propellant had a high response function under the conditions of high pressure (~11.5 MPa) and low frequency (~140 Hz). The numerically predicted oscillation frequency and amplitude are consistent with the experimental results. One practical solid rocket motor using this sample propellant was found to experience pressure oscillation at the end of burning. This confirms that the sample propellant is prone to combustion instability. Finally, acoustic pressure distribution and phase difference in T-burner were analyzed. Both the experimental and numerical results are found to be associated with similar acoustic pressure distribution. And the phase difference analysis showed that the pressure oscillations at the head end of the T-burner are 180° out of phase from those in the aft end of the T-burner.

  6. Abnormalities in intracellular calcium regulation and contractile function in myocardium from dogs with pacing-induced heart failure.

    PubMed Central

    Perreault, C L; Shannon, R P; Komamura, K; Vatner, S F; Morgan, J P

    1992-01-01

    24 d of rapid ventricular pacing induced dilated cardiomyopathy with both systolic and diastolic dysfunction in conscious, chronically instrumented dogs. We studied mechanical properties and intracellular calcium (Ca2+i) transients of trabeculae carneae isolated from 15 control dogs (n = 32) and 11 dogs with pacing-induced cardiac failure (n = 26). Muscles were stretched to maximum length at 30 degrees C and stimulated at 0.33 Hz; a subset (n = 17 control, n = 17 myopathic) was loaded with the [Ca2+]i indicator aequorin. Peak tension was depressed in the myopathic muscles, even in the presence of maximally effective (i.e., 16 mM) [Ca2+] in the perfusate. However, peak [Ca2+]i was similar (0.80 +/- 0.13 vs. 0.71 +/- 0.05 microM; [Ca2+]o = 2.5 mM), suggesting that a decrease in Cai2+ availability was not responsible for the decreased contractility. The time for decline from the peak of the Cai2+ transient was prolonged in the myopathic group, which correlated with prolongation of isometric contraction and relaxation. However, similar end-diastolic [Ca2+]i was achieved in both groups (0.29 +/- 0.05 vs. 0.31 +/- 0.02 microM), indicating that Cai2+ homeostasis can be maintained in myopathic hearts. The inotropic response of the myopathic muscles to milrinone was depressed compared with the controls. However, when cAMP production was stimulated by pretreatment with forskolin, the response of the myopathic muscles to milrinone was improved. Our findings provide direct evidence that abnormal [Ca2+]i handling is an important cause of contractile dysfunction in dogs with pacing-induced heart failure and suggest that deficient production of cAMP may be an important cause of these changes in excitation-contraction coupling. PMID:1311723

  7. Abnormalities in intracellular calcium regulation and contractile function in myocardium from dogs with pacing-induced heart failure

    NASA Technical Reports Server (NTRS)

    Perreault, C. L.; Shannon, R. P.; Komamura, K.; Vatner, S. F.; Morgan, J. P.

    1992-01-01

    24 d of rapid ventricular pacing induced dilated cardiomyopathy with both systolic and diastolic dysfunction in conscious, chronically instrumented dogs. We studied mechanical properties and intracellular calcium (Ca2+i) transients of trabeculae carneae isolated from 15 control dogs (n = 32) and 11 dogs with pacing-induced cardiac failure (n = 26). Muscles were stretched to maximum length at 30 degrees C and stimulated at 0.33 Hz; a subset (n = 17 control, n = 17 myopathic) was loaded with the [Ca2+]i indicator aequorin. Peak tension was depressed in the myopathic muscles, even in the presence of maximally effective (i.e., 16 mM) [Ca2+] in the perfusate. However, peak [Ca2+]i was similar (0.80 +/- 0.13 vs. 0.71 +/- 0.05 microM; [Ca2+]o = 2.5 mM), suggesting that a decrease in Cai2+ availability was not responsible for the decreased contractility. The time for decline from the peak of the Cai2+ transient was prolonged in the myopathic group, which correlated with prolongation of isometric contraction and relaxation. However, similar end-diastolic [Ca2+]i was achieved in both groups (0.29 +/- 0.05 vs. 0.31 +/- 0.02 microM), indicating that Cai2+ homeostasis can be maintained in myopathic hearts. The inotropic response of the myopathic muscles to milrinone was depressed compared with the controls. However, when cAMP production was stimulated by pretreatment with forskolin, the response of the myopathic muscles to milrinone was improved. Our findings provide direct evidence that abnormal [Ca2+]i handling is an important cause of contractile dysfunction in dogs with pacing-induced heart failure and suggest that deficient production of cAMP may be an important cause of these changes in excitation-contraction coupling.

  8. 42 CFR 460.50 - Termination of PACE program agreement.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... SERVICES (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) Sanctions, Enforcement Actions, and Termination § 460.50 Termination of...

  9. Temporary epicardial pacing wire placement in totally endoscopic cardiac surgery.

    PubMed

    Yu, Tao; Zhang, Xiaoshen; Huang, Keli

    2016-07-01

    Temporary epicardial pacing wire placement is a common procedure in cardiac surgery. However, it is difficult to perform in totally endoscopic cardiac surgery. We describe a simple new technique to place temporary epicardial pacing wires quickly and safely. PMID:27130494

  10. Coupled Integration of CSAC, MIMU, and GNSS for Improved PNT Performance

    PubMed Central

    Ma, Lin; You, Zheng; Liu, Tianyi; Shi, Shuai

    2016-01-01

    Positioning, navigation, and timing (PNT) is a strategic key technology widely used in military and civilian applications. Global navigation satellite systems (GNSS) are the most important PNT techniques. However, the vulnerability of GNSS threatens PNT service quality, and integrations with other information are necessary. A chip scale atomic clock (CSAC) provides high-precision frequency and high-accuracy time information in a short time. A micro inertial measurement unit (MIMU) provides a strap-down inertial navigation system (SINS) with rich navigation information, better real-time feed, anti-jamming, and error accumulation. This study explores the coupled integration of CSAC, MIMU, and GNSS to enhance PNT performance. The architecture of coupled integration is designed and degraded when any subsystem fails. A mathematical model for a precise time aiding navigation filter is derived rigorously. The CSAC aids positioning by weighted linear optimization when the visible satellite number is four or larger. By contrast, CSAC converts the GNSS observations to range measurements by “clock coasting” when the visible satellite number is less than four, thereby constraining the error divergence of micro inertial navigation and improving the availability of GNSS signals and the positioning accuracy of the integration. Field vehicle experiments, both in open-sky area and in a harsh environment, show that the integration can improve the positioning probability and accuracy. PMID:27187399

  11. Coupled Integration of CSAC, MIMU, and GNSS for Improved PNT Performance.

    PubMed

    Ma, Lin; You, Zheng; Liu, Tianyi; Shi, Shuai

    2016-01-01

    Positioning, navigation, and timing (PNT) is a strategic key technology widely used in military and civilian applications. Global navigation satellite systems (GNSS) are the most important PNT techniques. However, the vulnerability of GNSS threatens PNT service quality, and integrations with other information are necessary. A chip scale atomic clock (CSAC) provides high-precision frequency and high-accuracy time information in a short time. A micro inertial measurement unit (MIMU) provides a strap-down inertial navigation system (SINS) with rich navigation information, better real-time feed, anti-jamming, and error accumulation. This study explores the coupled integration of CSAC, MIMU, and GNSS to enhance PNT performance. The architecture of coupled integration is designed and degraded when any subsystem fails. A mathematical model for a precise time aiding navigation filter is derived rigorously. The CSAC aids positioning by weighted linear optimization when the visible satellite number is four or larger. By contrast, CSAC converts the GNSS observations to range measurements by "clock coasting" when the visible satellite number is less than four, thereby constraining the error divergence of micro inertial navigation and improving the availability of GNSS signals and the positioning accuracy of the integration. Field vehicle experiments, both in open-sky area and in a harsh environment, show that the integration can improve the positioning probability and accuracy. PMID:27187399

  12. Improving coupling of surface and groundwater for high resolution water cycle models

    NASA Astrophysics Data System (ADS)

    McIntyre, N.; Bulygina, N.; Butler, A. P.; Jackson, C. R.

    2012-12-01

    The JULES land surface model is widely used for global and regional scale water cycle modelling, and its hydrological component has been proposed as a potentially suitable for water resources and water quality modelling purposes. Current research is exploring the applicability of JULES at high resolution (e.g. 1km2) in terms of suitability of process representation, data needs and parameter estimation challenges. Our work on process representation research is focussing on improved coupling of groundwater models with JULES. Current operational versions of JULES include semi-empirical representations of saturated areas, using the probability distributed moisture (PDM) model and TOPMODEL. However these models do not attempt to provide realistic groundwater-unsaturated zone interactions or lateral movement of groundwater, and the empirical nature of these groundwater models also requires parameter calibration. All these limitations may become more relevant as model spatial resolutions become higher. We have coupled alternative groundwater models with JULES and tested the integrated models on the Kennet catchment, a mainly permeable subcatchment of the Thames basin in southern England. One of the integrated models uses a modification of the existing TOPMODEL that aims to provide an improved representation of the deep unsaturated zone; and the second uses the physics-based ZOOMQ3D groundwater model that aims to provide a realistic regional groundwater surface, groundwater level dynamics and lateral movement of groundwater. All are applied at the 1 x 1 km scale. Results for the Kennet for these coupled JULES-groundwater models are presented and performance is assessed relative to observations in terms of soil mositure and river flows. The models are critically discussed in terms of performance and potential range of applicability.

  13. Applying 20/20 Hindsight to Self-Pacing.

    ERIC Educational Resources Information Center

    Dunkleberger, Gary E.

    1980-01-01

    Discussed are several suggestions for the maintenance of a science self-paced classroom. Topics include the use of computers for student self-assessment, teachers and students roles in the self-paced classroom, and laboratory setup and packaging in the self-paced science laboratory. (Author/DS)

  14. His bundle pacing: Initial experience and lessons learned.

    PubMed

    Deshmukh, Amrish; Deshmukh, Pramod

    2016-01-01

    Direct His bundle pacing provides the most physiologic means of artificial pacing of the ventricles with a preserved His-Purkinje system and may play a role in patients with a diseased intrinsic conduction system. We describe our initial motivations and experience with permanent direct His bundle pacing and important lessons learned since that time. PMID:27591359

  15. Visual aided pacing in respiratory maneuvers

    NASA Astrophysics Data System (ADS)

    Rambaudi, L. R.; Rossi, E.; Mántaras, M. C.; Perrone, M. S.; Siri, L. Nicola

    2007-11-01

    A visual aid to pace self-controlled respiratory cycles in humans is presented. Respiratory manoeuvres need to be accomplished in several clinic and research procedures, among others, the studies on Heart Rate Variability. Free running respiration turns to be difficult to correlate with other physiologic variables. Because of this fact, voluntary self-control is asked from the individuals under study. Currently, an acoustic metronome is used to pace respiratory frequency, its main limitation being the impossibility to induce predetermined timing in the stages within the respiratory cycle. In the present work, visual driven self-control was provided, with separate timing for the four stages of a normal respiratory cycle. This visual metronome (ViMet) was based on a microcontroller which power-ON and -OFF an eight-LED bar, in a four-stage respiratory cycle time series handset by the operator. The precise timing is also exhibited on an alphanumeric display.

  16. State of the art of leadless pacing

    PubMed Central

    Sperzel, Johannes; Burri, Haran; Gras, Daniel; Tjong, Fleur V.Y.; Knops, Reinoud E.; Hindricks, Gerhard; Steinwender, Clemens; Defaye, Pascal

    2015-01-01

    Despite undisputable benefits, conventional pacemaker therapy is associated with specific complications related to the subcutaneous device and the transvenous leads. Recently, two miniaturized leadless pacemakers, Nanostim™ (St. Jude Medical) and Micra™ (Medtronic), which can be completely implanted inside the right ventricle using steerable delivery systems, entered clinical application. The WiCS™-cardiac resynchronisation therapy (CRT) system (wireless cardiac stimulation for CRT, EBR Systems) delivers leadless left ventricular endocardial stimulation for cardiac resynchronization. In addition to obvious cosmetic benefits, leadless pacing systems may have the potential to overcome some complications of conventional pacing. However, acute and long-term complications still remains to be determined, as well as the feasibility of device explantation years after device placement. PMID:26024918

  17. State of the art of leadless pacing.

    PubMed

    Sperzel, Johannes; Burri, Haran; Gras, Daniel; Tjong, Fleur V Y; Knops, Reinoud E; Hindricks, Gerhard; Steinwender, Clemens; Defaye, Pascal

    2015-10-01

    Despite undisputable benefits, conventional pacemaker therapy is associated with specific complications related to the subcutaneous device and the transvenous leads. Recently, two miniaturized leadless pacemakers, Nanostim™ (St. Jude Medical) and Micra™ (Medtronic), which can be completely implanted inside the right ventricle using steerable delivery systems, entered clinical application. The WiCS™-cardiac resynchronisation therapy (CRT) system (wireless cardiac stimulation for CRT, EBR Systems) delivers leadless left ventricular endocardial stimulation for cardiac resynchronization. In addition to obvious cosmetic benefits, leadless pacing systems may have the potential to overcome some complications of conventional pacing. However, acute and long-term complications still remains to be determined, as well as the feasibility of device explantation years after device placement. PMID:26024918

  18. Fabrication of improved SiGe alloys for an 18-couple module test

    NASA Astrophysics Data System (ADS)

    Loughin, S.; Nakahara, J. F.; Centurioni, D. X.; Cook, B. A.; Harringa, J. L.

    1995-02-01

    N- and p-type Si(0.78)Ge(0.22) alloys were fabricated to determine if recently reported improvements in the figure-of-merit, Z, could be realized in devices. These will be tested in an 18-couple module to directly compare the performance of these materials with that of standard coarse-grain SiGe used in flight programs. We describe the synthesis by vacuum casting and hot pressing p-type SiGe and mechanical alloying and hot-isostatic pressing n-type SiGe. Improved materials and standard materials are characterized and compared. The integrated average figures-of-merit (573-1273 K) of the improved materials were Z(sub p) = 0.59 x 10(exp -3) K(sup -1) and Z(sub n) = 0.85 x 10(exp -3) K(sup -1) compared with Z(sub p) = 0.52 x 10(exp -1) K(sup -1) and Z(sub n) = 0.76 x 10(exp -3) K(sup -1) for the standard materials. We also report the power factors for improved and standard materials removed from fabricated devices to gain insight as to how subsequent processing impacts performance.

  19. Fabrication of improved SiGe alloys for an 18-couple module test

    SciTech Connect

    Loughin, S.; Nakahara, J.F.; Centurioni, D.X.; Cook, B.A.; Harringa, J.L.

    1995-01-01

    N- and p-type Si{sub 0.78}Ge{sub 0.22} alloys were fabricated to determine if recently reported improvements in the figure-of-merit, Z, could be realized in devices. These will be tested in an 18-couple module to directly compare the performance of these materials with that of standard coarse-grain SiGe used in flight programs. We describe the synthesis by vacuum casting and hot pressing p-type SiGe and mechanical alloying and hot-isostatic pressing n-type SiGe. Improved materials and standard materials are characterized and compared. The integrated average figures-of-merit (573--1273 K) of the improved materials were Z{sub p} = 0.59 {times} 10{sup {minus}3} K{sup {minus}1} and Z{sub n} = 0.85 {times} 10{sup {minus}3} K{sup {minus}1} compared with Z{sub p} = 0.52 {times} l0{sup {minus}3} K{sup {minus}1} and Z{sub n} = 0.76 {times} 10{sup {minus}3} K{sup {minus}1} for the standard materials. We also report the power factors for improved and standard materials removed from fabricated devices to gain insight as to how subsequent processing impacts performance.

  20. Cardiac resynchronisation therapy in 2015: keeping up with the pace.

    PubMed

    Voskoboinik, A; McGavigan, A D; Mariani, J A

    2016-03-01

    Despite improved understanding of the pathophysiology of heart failure (HF) and availability of better medical therapies, HF continues to grow as a cause of morbidity and mortality in Australia and worldwide. Over the past decade, cardiac resynchronisation therapy (CRT), or biventricular pacing, has been embraced as a powerful weapon against this growing epidemic. However, much has changed in our understanding of dyssynchrony in HF, and this has led to a change in guidelines to ensure more appropriate selection of CRT candidates to improve the 'non-response' rate. More data have also emerged about the use of CRT in atrial fibrillation and in pacemaker-dependent patients. There has also been a growing focus on multimodality imaging to guide patient selection and lead positioning. Exciting new lead technologies are also emerging, with the potential to improve CRT outcomes further. PMID:25851588

  1. Gait Alterations During Constant Pace Treadmill Racewalking.

    PubMed

    Hanley, Brian

    2015-08-01

    Racewalking is an Olympic event requiring great endurance, and racewalkers often use treadmills in training because of the benefits of having a flat unchanging surface where pace judgment can be learned and because inclement weather can be avoided. The effects of fatigue associated with racewalking on a treadmill have not been studied and could be informative with regard to the maintenance of legal technique. The aim of this study was to measure key gait variables during a physically demanding treadmill racewalk. Fourteen international racewalkers completed 10 km on an instrumented treadmill at a pace equivalent to 103% of their recent best time. Spatiotemporal and ground reaction force data were recorded at 4 distances. High-speed videography data were simultaneously recorded to analyze changes in knee angle between the early and late stages. Increases in step length and corresponding decreases in cadence were found, although the small changes were not considered meaningful. There was also a small increase in flight time and a small decrease in push-off force. There were no other significant changes for any other variables (including knee angles). The increase in flight time might be important given that racewalkers are not permitted a visible loss of contact and suggests that fatiguing sessions on a treadmill can lead to the adoption of nonlegal technique. However, this disadvantage of treadmill training can be negated if the coach scrutinizes athletes throughout the session, and overall the consistent technique used is of benefit with regard to learning correct form and pacing ability. PMID:25647657

  2. Interfacial coupling between immiscible polymers: Flow accelerates reaction and improves adhesion

    NASA Astrophysics Data System (ADS)

    Song, Jie

    As the workhorses of the plastics industry, polyolefins are consumed in the largest volume of all types of polymers. Despite their wide use, polyolefins suffer from poor adhesion and compatibility with other polar polymers due to their intrinsic low polarity and lack of functional groups. The first goal of this study is to enhance interfacial adhesion between polyolefins with other polymers through coupling reaction of functional polymers. We have used functional polyethylenes with maleic anhydride, hydroxyl, primary and secondary amino groups grafted through reactive extrusion. Functional polyolefins dramatically improved the performance of polyolefins, including adhesion, compatibility, hardness and scratch resistance, and greatly expand their applications. The second goal is to understand the factors affecting adhesion. We systematically investigated two categories of parameters. One is molecular: the type and incorporation level of functional groups. The other is processing condition: die design in extruders, reaction time and temperature. The interfacial adhesion was measured with the asymmetric dual cantilever beam test and T-peel test. The extent of reaction was quantified through measuring anchored copolymers via X-ray photoelectron spectroscopy. A quantitative correlation between adhesion and coupling reaction was developed. A coextruded bilayer system with coupling reaction at interfaces was created to clarify processing effects on the kinetics of coupling reactions. For the reaction between maleic anhydride modified polyethylene and nylon 6, the reaction rate during coextrusion through a fishtail die with compressive/extensional flow was strikingly almost two orders of magnitude larger than that through a constant thickness die without compressive flow. The latter reaction rate was close to that of quiescent lamination. We attribute the reaction acceleration through the fishtail die to the large deformation rate under the compressive/extensional flow

  3. An Exploratory Study of Student-Paced versus Teacher-Paced Accommodations for Large-Scale Math Tests.

    ERIC Educational Resources Information Center

    Hollenbeck, Keith; Rozek-Tedesco, Marick A.; Tindal, Gerald; Glasgow, Aaron

    2000-01-01

    This study examined whether a teacher-paced video (TPV) accommodation or a student-paced computer (SPC) accommodation provided differential access for student with disabilities versus their general education peers on a large-scale math test. It found that although both pacing accommodations significantly influenced mean scores, the SPC…

  4. Optical stimulation enables paced electrophysiological studies in embryonic hearts

    PubMed Central

    Wang, Yves T.; Gu, Shi; Ma, Pei; Watanabe, Michiko; Rollins, Andrew M.; Jenkins, Michael W.

    2014-01-01

    Cardiac electrophysiology plays a critical role in the development and function of the heart. Studies of early embryonic electrical activity have lacked a viable point stimulation technique to pace in vitro samples. Here, optical pacing by high-precision infrared stimulation is used to pace excised embryonic hearts, allowing electrophysiological parameters to be quantified during pacing at varying rates with optical mapping. Combined optical pacing and optical mapping enables electrophysiological studies in embryos under more physiological conditions and at varying heart rates, allowing detection of abnormal conduction and comparisons between normal and pathological electrical activity during development in various models. PMID:24761284

  5. Fundamental and methodological investigations for the improvement of elemental analysis by inductively coupled plasma mass soectrometry

    SciTech Connect

    Ebert, Christopher Hysjulien

    2012-01-01

    This dissertation describes a variety of studies meant to improve the analytical performance of inductively coupled plasma mass spectrometry (ICP-MS) and laser ablation (LA) ICP-MS. The emission behavior of individual droplets and LA generated particles in an ICP is studied using a high-speed, high frame rate digital camera. Phenomena are observed during the ablation of silicate glass that would cause elemental fractionation during analysis by ICP-MS. Preliminary work for ICP torch developments specifically tailored for the improvement of LA sample introduction are presented. An abnormal scarcity of metal-argon polyatomic ions (MAr{sup +}) is observed during ICP-MS analysis. Evidence shows that MAr{sup +} ions are dissociated by collisions with background gas in a shockwave near the tip of the skimmer cone. Method development towards the improvement of LA-ICP-MS for environmental monitoring is described. A method is developed to trap small particles in a collodion matrix and analyze each particle individually by LA-ICP-MS.

  6. European clinical experience with a dual chamber single pass sensing and pacing defibrillation lead.

    PubMed

    Gradaus, Rainer; Gonska, Bernd D; Stellbrink, Christoph; Cron, Thomas; Tebbenjohanns, Jürgen; Blomström-Lundqvist, Carina; Himmrich, Ewald; Salerno, Jorge A; Osswald, Stefan; Gommer, Erik D; Van Veen, Benno K; Böcker, Dirk

    2002-07-01

    Dual chamber ICDs are increasingly implanted nowadays, mainly to improve discrimination between supraventricular and ventricular arrhythmias but also to maintain AV synchrony in patients with bradycardia. The aim of this study was to investigate a new single pass right ventricular defibrillation lead capable of true bipolar sensing and pacing in the right atrium and integrated bipolar sensing and pacing in the right ventricle. The performance of the lead was evaluated in 57 patients (age 61 +/- 12 years; New York Heart Association 1.9 +/- 0.6, left ventricular ejection fraction 0.38 +/- 0.15) at implant, at prehospital discharge, and during a 1-year follow-up. Sensing and pacing behavior of the lead was evaluated in six different body positions. In four patients, no stable position of the atrial electrode could intraoperatively be found. The intraoperative atrial sensing was 2.3 +/- 1.6 mV and the atrial pacing threshold 0.8 +/- 0.5 V at 0.5 ms. At follow-up, the atrial sensing ranged from 1.5 mV to 2.2 mV and the atrial pacing threshold product from 0.8 to 1.7 V/ms. In 11 patients, an intermittent atrial sensing problem and in 24 patients an atrial pacing dysfunction were observed in at least one body position. In 565 episodes, a sensitivity of 100% and a specificity of 96.5% were found for ventricular arrhythmias. In conclusion, this single pass defibrillation lead performed well as a VDD lead and for dual chamber arrhythmia discrimination. However, loss of atrial capture in 45% of patients preclude its use in patients depending on atrial pacing. PMID:12164450

  7. Single pass lead VDD pacing in children and adolescents.

    PubMed

    Rosenheck, S; Elami, A; Amikam, S; Erdman, S; Ovsyshcher, I E

    1997-08-01

    Implantation of permanent pacemakers in children and adolescents is possible but usually is limited to single chamber generators. The natural growth of these patients may require physiological pacing, but until recently two leads were required for this type of pacing. The single pass lead VDD pacing mode makes possible physiological pacing by using only one lead, for both atrial sensing and ventricular sensing and pacing. The feasibility of VDD pacing using endocardial lead was evaluated in 16 children and adolescents with congenital or postsurgical atrioventricular block. Their mean age was 7.9 +/- 4.9 years (range 1-16 years) and the smallest patient's weight was 8.2 kg. In all the patients, a single pass pacing lead with atrial sensing rings and bipolar ventricular pacing and sensing capability was implanted through the left or right subclavian vein. The pacemaker generator was implanted in a rectopectoral position. The mean atrial electrogram during the implantation was 4.2 +/- 2.1 mV and 2.6 +/- 1.9 mV after a mean of 1 week. The ventricular pacing threshold was 0.5 +/- 0.2 V; the ventricular pacing impedance was 560 +/- 95 omega; and the ventricular electrogram amplitude was 9.9 +/- 2.1 mV. This is a first report to demonstrate the feasibility of atrial synchronous ventricular endocardial pacing using a single pass lead in a relatively large group of children and adolescents. PMID:9272534

  8. 42 CFR 460.90 - PACE benefits under Medicare and Medicaid.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... SERVICES (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PACE Services § 460.90 PACE benefits under Medicare and Medicaid. If a...

  9. 42 CFR 460.90 - PACE benefits under Medicare and Medicaid.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... SERVICES (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PACE Services § 460.90 PACE benefits under Medicare and Medicaid. If a...

  10. 42 CFR 460.32 - Content and terms of PACE program agreement.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... SERVICES (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PACE Program Agreement § 460.32 Content and terms of PACE program agreement....

  11. 42 CFR 460.90 - PACE benefits under Medicare and Medicaid.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... SERVICES (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PACE Services § 460.90 PACE benefits under Medicare and Medicaid. If a...

  12. 42 CFR 460.32 - Content and terms of PACE program agreement.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... SERVICES (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PACE Program Agreement § 460.32 Content and terms of PACE program agreement....

  13. 42 CFR 460.32 - Content and terms of PACE program agreement.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... SERVICES (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PACE Program Agreement § 460.32 Content and terms of PACE program agreement....

  14. 42 CFR 460.32 - Content and terms of PACE program agreement.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... SERVICES (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PACE Program Agreement § 460.32 Content and terms of PACE program agreement....

  15. 42 CFR 460.90 - PACE benefits under Medicare and Medicaid.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... SERVICES (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PACE Services § 460.90 PACE benefits under Medicare and Medicaid. If a...

  16. 42 CFR 460.32 - Content and terms of PACE program agreement.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... SERVICES (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PACE Program Agreement § 460.32 Content and terms of PACE program agreement....

  17. Mapping of Regional Myocardial Strain and Work During Ventricular Pacing

    PubMed Central

    Prinzen, Frits W.; Hunter, William C.; Wyman, Bradley T.; McVeigh, Elliot R.

    2007-01-01

    OBJECTIVES The purpose of this study was to determine the spatial distribution of myocardial function (myofiber shortening and work) within the left ventricular (LV) wall during ventricular pacing. BACKGROUND Asynchronous electrical activation, as induced by ventricular pacing, causes various abnormalities in LV function, perfusion and structure. These derangements may be caused by abnormalities in regional contraction patterns. However, insight into these patterns during pacing is as yet limited. METHODS In seven anesthetized dogs, high spatial and temporal resolution magnetic resonance-tagged images were acquired in three orthogonal planes. Three-dimensional deformation data and LV cavity pressure and volume were used to determine midwall circumferential strain and external and total mechanical work at 192 sites around the left ventricle. RESULTS During ventricular pacing, systolic fiber strain and external work were approximately zero in regions near the pacing site, and gradually increased to more than twice the normal value in the most remote regions. Total mechanical work, normalized to the value during right atrial pacing, was 38 ± 13% (right ventricular apex [RVapex] pacing) and 61 ± 23% (left ventricular base [LVbase] pacing) close to the pacing site, and 125 ± 48% and 171 ± 60% in remote regions, respectively (p < 0.05 between RVapex and LVbase pacing). The number of regions with reduced work was significantly larger during RVapex than during LVbase pacing. This was associated with a reduction of global LV pump function during RVapex pacing. CONCLUSIONS Ventricular pacing causes a threefold difference in myofiber work within the LV wall. This difference appears large enough to regard local myocardial function as an important determinant for abnormalities in perfusion, metabolism, structure and pump function during asynchronous electrical activation. Pacing at sites that cause more synchronous activation may limit the occurrence of such derangements

  18. Right ventricle bipolar pacing may prevent appropriate biventricular pacing from two pacemakers. Case report.

    PubMed

    Kranidis, Athanasios I; Andrikopoulos, George K; Kappos, Kostas G; Bouki, Tania P; Dedehlias, Panos N

    2004-10-01

    This article reports on practical problems and possible solutions that may occur in case of upgrading a dual-chamber pacemaker by implanting a second left ventricular ventricular pacing, ventricular sensing, ventricular triggering (VVT) pacemaker. This therapeutic strategy was considered appropriate in the case of a 73-year-old patient with severe heart failure, who was scheduled to undergo coronary artery bypass surgery. A right-sided, dual-chamber pacemaker had been already implanted to the patient. The duration of the paced QRS complex was 220 ms and inter- and intraventricular dyssynchrony was documented in the echocardiographic study. We describe the methodological problems and possible solutions related to biventricular pacing following the abovementioned strategy. PMID:15484162

  19. Improved Arterial–Ventricular Coupling in Metabolic Syndrome after Exercise Training

    PubMed Central

    Fournier, Sara B.; Donley, David A.; Bonner, Daniel E.; DeVallance, Evan; Olfert, I. Mark; Chantler, Paul D.

    2014-01-01

    Purpose The metabolic syndrome (MetS) is associated with a three-fold increase risk of cardiovascular (CV) morbidity and mortality, which is in part, due to a blunted CV reserve capacity, reflected by a reduced peak exercise left ventricular contractility and aerobic capacity, and a blunted peak arterial-ventricular coupling. To date, no study has examined whether aerobic exercise training in MetS can reverse the peak exercise CV dysfunction. Further, examining how exercise training alters CV function in a group of individuals with MetS prior to the development of diabetes and/or overt CVD, can provide insights into whether some of the pathophysiological changes to the CV can be delayed/reversed, lowering their CV risk. The objective of this study was to examine the effects of 8 weeks of aerobic exercise training in individuals with MetS on resting and peak exercise CV function. Methods Twenty MetS underwent either 8 weeks of aerobic exercise training (MetS-ExT; n=10) or remained sedentary (MetS-NonT; n=10) during this time period. Resting and peak exercise CV function was characterized using Doppler echocardiography and gas exchange. Results Exercise training did not alter resting left ventricular diastolic or systolic function and arterial-ventricular coupling in MetS. In contrast, at peak exercise an increase in LV contractility (40%, p<0.01), cardiac output (28%, p<0.05) and aerobic capacity (20%, p<0.01), while a reduction in vascular resistance (30%, p<0.05) and arterial-ventricular coupling (27%, p<0.01), were noted in the MetS-ExT but not the MetS-NonT group. Further, an improvement in Lifetime Risk Score was also noted in the MetS-ExT group. Conclusions These findings have clinical importance as they provide insight that some of the pathophysiological changes associated with MetS can be improved and lower the risk of CVD. PMID:24870568

  20. Comparison of effectiveness of right ventricular septal pacing versus right ventricular apical pacing.

    PubMed

    Cano, Oscar; Osca, Joaquín; Sancho-Tello, María-José; Sánchez, Juan M; Ortiz, Víctor; Castro, José E; Salvador, Antonio; Olagüe, José

    2010-05-15

    Chronic right ventricular apical pacing (RVAP) has been associated with negative hemodynamic and clinical effects. The aim of the present study was to compare RVAP with right ventricular septal pacing (RVSP) in terms of echocardiographic features and clinical outcomes. A total of 93 patients without structural heart disease and with an indication for a permanent pacemaker were randomly assigned to receive a screw-in lead either in the RV apex (n = 46) or in the RV mid-septum (n = 47). The patients were divided into 3 subgroups according to the percentage of ventricular pacing: control group (n = 21, percentage of ventricular pacing < or =10%), RVAP group (n = 28), or RVSP group (n = 32; both latter groups had a percentage of ventricular pacing >10%). The RVAP group had more intraventricular dyssynchrony and a trend toward a worse left ventricular ejection fraction compared to the RVSP and control groups at 12 months of follow-up (maximal delay to peak systolic velocity between any of the 6 left ventricular basal segments was 57.8 +/- 38.2, 35.5 +/- 20.6, and 36.5 +/- 17.8 ms for RVAP, RVSP, and control group, respectively; p = 0.006; mean left ventricular ejection fraction 62.9 +/- 7.9%, 66.5 +/- 7.2%, and 66.6 +/- 7.2%, respectively, p = 0.14). Up to 48.1% of the RVAP patients showed significant intraventricular dyssynchrony compared to 19.4% of the RVSP patients and 23.8% of the controls (p = 0.04). However, no overt clinical benefits from RVSP were found. In conclusion, RVAP was associated with increased dyssynchrony compared to the RVSP and control patients. RVSP could represent an alternative pacing site in selected patients to reduce the harmful effects of traditional RVAP. PMID:20451689

  1. Benefit of single setting rate responsive ventricular pacing compared with fixed rate demand pacing in elderly patients.

    PubMed

    Gammage, M; Schofield, S; Rankin, I; Bennett, M; Coles, P; Pentecost, B

    1991-02-01

    In order to assess the value of a simple, single setting rate response option to VVI pacing, 12 patients (mean age 75.1 +/- 6.2, range 62-83 years, seven males, five females) with symptomatic complete heart block were entered into a double-blind, randomized crossover trial of VVI versus VVIR (single setting rate responsive) pacing using Medtronic Activitrax pacemakers. Assessment was by time taken in seconds (sec) and Borg scale symptom score (6-20) for simple activities (standing from chair x 30; walking 800 meters; 52 steps on stairs [slow and fast pace], and incremental, noninclined maximal treadmill exercise), performed after a 4-week period with the patient in each pacing mode. Times were significantly improved in VVIR mode for standing from chair [mean +/- SD] (78.7 +/- 22.5 vs 70.7 +/- 19.5 sec; P less than 0.05), for 800 m walk (1032 +/- 80 vs 885 +/- 59 sec; P less than 0.05), fast ascent of stairs (29.5 +/- 7.7 vs 26.5 +/- 5.6 sec; P less than 0.02), and treadmill exercise (626.7 +/- 189.5 vs 741.0 +/- 170.2 sec, P less than 0.005) although no difference in time for slow stair ascent was demonstrated. Symptom scores were significantly less in VVIR for standing from chair (12.7 +/- 2.8 vs 10.3 +/- 1.8; P less than 0.01), 800 m walk (10.9 +/- 2.7 vs 9.0 +/- 2.4; P less than 0.01), slow ascent of stairs (11.6 +/- 2.1 vs 10.0 +/- 2.0; P less than 0.01), and fast ascent of stairs (13.0 +/- 2.0 vs 11.7 +/- 1.9; P less than 0.02) but unchanged for treadmill exercise.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1706502

  2. Aliskiren protecting atrial structural remodeling from rapid atrial pacing in a canine model.

    PubMed

    Zhao, Zhiqiang; Chen, Yan; Li, Weimin; Wang, Xinghua; Li, Jian; Yang, Wansong; Cheng, Lijun; Liu, Tong; Liu, Enzhao; Li, Guangping

    2016-08-01

    Atrial fibrillation (AF) contributing to the increasing mortality risk is the most common disease in clinical practice. Owing to the side effects and relative inefficacy of current antiarrhythmic drugs, some research focuses on renin-angiotensin-aldosterone system (RAS) for finding out the new treatment of AF. The purpose of this study is to confirm whether aliskiren as a proximal inhibitor of renin, which completely inhibits RAS, has beneficial effects on atrial structural remodeling in AF. In this study, rapid atrial pacing was induced at 500 beats per minute for 2 weeks in a canine model. A different dose of aliskiren was given orally for 2 weeks before rapid atrial pacing. HE staining and Masson's staining were used for analysis of myocardial fibrosis. TGF-β1, signal pathways, and pro-inflammatory cytokines were shown for the mechanism of structural remodeling after the treatment of aliskiren. Serious atrial fibrosis was induced by rapid atrial pacing, followed by the elevated TGF-β1, upregulated MEK and ERK1/2, and increased inflammatory factors. Aliskiren could apparently improve myocardial fibrosis by reducing the expression of TGF-β1, inhibiting MEK and ERK1/2 signal pathways, and decreasing IL-18 and TLR4 in both serum and atrial tissue. In conclusion, aliskiren could prevent atrial structural remodeling from rapid atrial pacing for 2 weeks. Aliskiren may play a potential beneficial role in the treatment of AF induced by rapid atrial pacing. PMID:27118660

  3. A biophysically based finite-state machine model for analyzing gastric experimental entrainment and pacing recordings.

    PubMed

    Sathar, Shameer; Trew, Mark L; Du, Peng; O'Grady, Greg; Cheng, Leo K

    2014-04-01

    Gastrointestinal motility is coordinated by slow waves (SWs) generated by the interstitial cells of Cajal (ICC). Experimental studies have shown that SWs spontaneously activate at different intrinsic frequencies in isolated tissue, whereas in intact tissues they are entrained to a single frequency. Gastric pacing has been used in an attempt to improve motility in disorders such as gastroparesis by modulating entrainment, but the optimal methods of pacing are currently unknown. Computational models can aid in the interpretation of complex in vivo recordings and help to determine optimal pacing strategies. However, previous computational models of SW entrainment are limited to the intrinsic pacing frequency as the primary determinant of the conduction velocity, and are not able to accurately represent the effects of external stimuli and electrical anisotropies. In this paper, we present a novel computationally efficient method for modeling SW propagation through the ICC network while accounting for conductivity parameters and fiber orientations. The method successfully reproduced experimental recordings of entrainment following gastric transection and the effects of gastric pacing on SW activity. It provides a reliable new tool for investigating gastric electrophysiology in normal and diseased states, and to guide and focus future experimental studies. PMID:24276722

  4. Application of PACE Principles for Population Health Management of Frail Older Adults.

    PubMed

    Stefanacci, Richard G; Reich, Shelley; Casiano, Alex

    2015-10-01

    To determine which practices would have the most impact on reducing hospital and emergency department admissions and nursing home placement among older adults with multiple comorbid conditions, a literature search and survey were conducted to identify and prioritize comprehensive care principles as practiced in the Program of All-inclusive Care for the Elderly (PACE). PACE medical directors and members of the PACE interdisciplinary team (IDT) were surveyed to gain their insights on the most impactful practices, which were identified as: End-of-Life Management, Caregiver Support, Management of Red Flags, Medication Management, Participant and Caregiver Health Care System Literacy, and Care Coordination. In addition, this research evaluated measures that could be used to assess an organization's level of success with regard to each of the 6 PACE practices identified. The results reported in this article, found through a survey with PACE medical directors and IDT members concerning effective interventions, can be viewed as strategies to improve care for older adults, enabling them to maintain their independence in the community, avoid the expense of facility-based care, and enhance their quality of life. PMID:25647691

  5. Maine PACE Program Final Technical Report

    SciTech Connect

    Fischer, Dana; Adamson, Joy M

    2015-01-30

    The ARRA EECBG BetterBuilding helped augment the existing Home Energy Savings Programs (HESP) and incentives with financing through a subordinate lien PACE and HUD PowerSaver programs. The program was designed to document innovative techniques to dramatically increase the number of homes participating in weatherization programs in participating towns. Maine will support new energy efficiency retrofit pilots throughout the state, designed to motivate a large number of homeowners to invest in comprehensive home energy efficiency upgrades to bring real solutions to market.

  6. Influence of cinnamon and catnip on the stereotypical pacing of oncilla cats (Leopardus tigrinus) in captivity.

    PubMed

    Resende, Letícia de S; Pedretti Gomes, Karla C; Andriolo, Artur; Genaro, Gelson; Remy, Gabriella L; Almeida Ramos, Valdir de

    2011-01-01

    Nonhuman animals in captivity can experience environmental privation that results in their exhibiting abnormal behaviors. Environmental enrichment techniques can help improve their welfare. This study investigated the behavior of 8 zoo-housed oncilla cats (Leopardus tigrinus) in response to 2 odors (catnip and cinnamon) introduced individually into the animals' enclosures for 3 consecutive days. Proportion of scans spent engaging in stereotypical pacing were compared before, during, and after treatments. The addition of cinnamon reduced the proportion of pacing during and after enrichment (Wilcoxon: Z = 3.16, p < .001; Z = 3.16, p < .001, respectively), indicating a prolonged effect of the enrichment on the animals' behavior. Catnip appears to have elicited no significant difference in the stereotypic pacing before, during, or after the enrichment (Friedman: X(2) = 2.69; p = .260). The results highlight the potential use of cinnamon as a method of environmental enrichment for small captive-housed cats. PMID:22044295

  7. A gastroesophageal electrode for atrial and ventricular pacing.

    PubMed

    McEneaney, D J; Cochrane, D J; Anderson, J A; Adgey, A A

    1997-07-01

    Temporary transvenous cardiac pacing requires technical expertise and access to fluoroscopy. We have developed a gastroesophageal electrode capable of atrial and ventricular pacing. The flexible polythene gastroesophageal electrode is passed into the stomach under light sedation. Five ring electrodes, now positioned in the lower esophagus, are used for atrial pacing. A point source (cathode) on the distal tip of the electrode, now positioned in the gastric fundus, is used for ventricular pacing. Two configurations of atrial and ventricular pacing were compared: unipolar and bipolar. During unipolar ventricular pacing the indifferent electrode (anode) was a high impedance chest pad. For bipolar ventricular pacing the indifferent electrode was a ring electrodes placed 2 cm proximal to the tip. Unipolar atrial pacing was performed with 1 of 5 proximal ring electrodes acting as cathode ("cathodic") or as anode ("anodic") in conjunction with a chest pad. Bipolar atrial pacing was performed using combinations of 2 of 5 ring electrodes. Atrial capture was obtained in all 55 subjects attempted. When all electrode combinations were compared, atrial capture was significantly more frequent using the bipolar approach (153/210 bipolar, 65/210 unipolar; t = 7.37, P < 0.001). For unipolar atrial pacing, cathodic stimulation (from esophagus) was more successful than anodic stimulation (cathodic 62/105, anodic 20/105; t = 5.81, P < 0.001). In 43 subjects attempted unipolar ventricular pacing resulted in a higher frequency of capture than the bipolar approach (unipolar 41/43 (95.3%), bipolar 19/43 (44.2%); P < 0.001). In conclusion, atrial pacing was optimal using pairs of ring electrodes ("bipolar") while ventricular pacing was optimal using the distal electrode tip (cathode) in conjunction with a chest pad electrode ("unipolar"). This gastroesophageal electrode may be useful in the emergency management of acute bradyarrhythmias and for elective electrophysiological studies. PMID

  8. Scutellarin promotes microglia-mediated astrogliosis coupled with improved behavioral function in cerebral ischemia.

    PubMed

    Fang, Ming; Yuan, Yun; Lu, Jia; Li, Hong E; Zhao, Min; Ling, Eng-Ang; Wu, Chun-Yun

    2016-07-01

    Scutellarin, an anti-inflammatory agent, has been reported to suppress microglia activation. It promotes astrocytic reaction but through activated microglia. Here we sought to determine more specifically the outcomes of scutellarin treatment in reactive astrocytes in rats subjected to middle cerebral artery occlusion (MCAO). GFAP, MAP-2 and PSD-95 expression was assessed in reactive astrocytes in scutellarin injected MCAO rats. Expression of BDNF, NT-3 and IGF-1, and cell cycle markers cyclin-D1/B1 was also evaluated. In vitro, the above-mentioned proteins were also investigated in TNC 1 and primary astrocytes, treated respectively with conditioned medium from BV-2 microglia with or without pretreatment of scutellarin and lipopolysaccharide. Behavioral study was conducted to ascertain if scutellarin would improve the neurological functions of MCAO rats. In MCAO, reactive astrocytes in the penumbral areas were hypertrophic bearing long extending processes; expression of all the above-mentioned markers was markedly augmented. When compared to the controls, TNC1/primary astrocytes responded vigorously to conditioned medium derived from BV-2 microglia treated with scutellarin + lipopolysaccharide as shown by enhanced expression of all the above markers by Western and immunofluorescence analysis. By electron microscopy, hypertrophic TNC1 astrocytes in this group showed abundant microfilaments admixed with microtubules. In MCAO rats given scutellarin treatment, neurological scores were significantly improved coupled with a marked decrease in infarct size when compared with the matching controls. It is concluded that scutellarin is neuroprotective and that it can amplify astrogliosis but through activated microglia. Scutellarin facilitates tissue remodeling in MCAO that maybe linked to improvement of neurological functions. PMID:27105682

  9. Restructuring VA ambulatory care and medical education: the PACE model of primary care.

    PubMed

    Cope, D W; Sherman, S; Robbins, A S

    1996-07-01

    The Veterans Health Administration (VHA) Western Region and associated medical schools formulated a set of recommendations for an improved ambulatory health care delivery system during a 1988 strategic planning conference. As a result, the Department of Veterans Affairs (VA) Medical Center in Sepulveda, California, initiated the Pilot (now Primary) Ambulatory Care and Education (PACE) program in 1990 to implement and evaluate a model program. The PACE program represents a significant departure from traditional VA and non-VA academic medical center care, shifting the focus of care from the inpatient to the outpatient setting. From its inception, the PACE program has used an interdisciplinary team approach with three independent global care firms. Each firm is interdisciplinary in composition, with a matrix management structure that expands role function and empowers team members. Emphasis is on managed primary care, stressing a biopsychosocial approach and cost-effective comprehensive care emphasizing prevention and health maintenance. Information management is provided through a network of personal computers that serve as a front end to the VHA Decentralized Hospital Computer Program (DHCP) mainframe. In addition to providing comprehensive and cost-effective care, the PACE program educates trainees in all health care disciplines, conducts research, and disseminates information about important procedures and outcomes. Undergraduate and graduate trainees from 11 health care disciplines rotate through the PACE program to learn an integrated approach to managed ambulatory care delivery. All trainees are involved in a problem-based approach to learning that emphasizes shared training experiences among health care disciplines. This paper describes the transitional phases of the PACE program (strategic planning, reorganization, and quality improvement) that are relevant for other institutions that are shifting to training programs emphasizing primary and ambulatory care

  10. Investigating the use of coupling agents to improve the interfacial properties between a resorbable phosphate glass and polylactic acid matrix.

    PubMed

    Hasan, Muhammad Sami; Ahmed, Ifty; Parsons, Andrew J; Rudd, Chris D; Walker, Gavin S; Scotchford, Colin A

    2013-09-01

    Eight different chemicals were investigated as potential candidate coupling agents for phosphate glass fibre reinforced polylactic acid composites. Evidence of reaction of the coupling agents with phosphate glass and their effect on surface wettability and glass degradation were studied along with their principle role of improving the interface between glass reinforcement and polymer matrix. It was found that, with an optimal amount of coupling agent on the surface of the glass/polymer, interfacial shear strength improved by a factor of 5. Evidence of covalent bonding between agent and glass was found for three of the coupling agents investigated, namely: 3-aminopropyltriethoxysilane; etidronic acid and hexamethylene diisocyanate. These three coupling agents also improved the interfacial shear strength and increased the hydrophobicity of the glass surface. It is expected that this would provide an improvement in the macroscopic properties of full-scale composites fabricated from the same materials which may also help to retain these properties for the desired length of time by retarding the breakdown of the fibre/matrix interface within these composites. PMID:22781920

  11. Vocalization and pauses in fast-paced reading.

    PubMed

    Breznitz, Z

    1990-04-01

    Previous research (Breznitz, 1987a) indicated that prompting first-graders to read faster than usual increases their comprehension. The present study was conducted to clarify which of the speech elements that comprise reading time is affected when reading pace is accelerated. First-graders (N = 76) read aloud three parallel forms of a comprehension test, at self- and fast-paced rates consecutively, followed by a second self-paced reading. Vocalization time, pause time, pause frequency, and the average length of vocalizations and pauses were determined with an automatic vocal transaction analyzer. During fast-paced reading, children made fewer and shorter pauses, vocalized at a faster rate, and tended to speak in longer units. The speech characteristics indicative of fast-paced reading were significantly correlated with reading comprehension, even during self-paced reading, and can serve as indicators of effective reading. PMID:2366048

  12. An improved coupling model for the lithosphere-atmosphere-ionosphere system

    NASA Astrophysics Data System (ADS)

    Kuo, C. L.; Lee, L. C.; Huba, J. D.

    2014-04-01

    In our previous model for the lithosphere-atmosphere-ionosphere coupling, the background magnetic field was assumed to be perpendicular to the horizontal plane. In the present paper, we improve the calculation of currents in the atmosphere by solving the current density J directly from the current continuity equation ∇ • J = 0. The currents in the atmosphere can be solved for any arbitrary angle of magnetic field, i.e., any magnetic latitude. In addition, a large ratio (~10) of Hall to Pedersen conductivities is used to generate a large Hall electric field. The effects of atmospheric currents and electric fields on the ionosphere with lithosphere current source located at magnetic latitudes of 7.5°, 15°, 22.5°, and 30° are obtained. For upward (downward) atmospheric currents flowing into the ionosphere, the simulation results show that the westward (eastward) electric fields dominate. At magnetic latitude of 7.5° or 15°, the upward (downward) current causes the increase (decrease) of total electron content (TEC) near the source region, while the upward (downward) current causes the decrease (increase) of TEC at magnetic latitude of 22.5°or 30°. The dynamo current density required to generate the same amount of TEC variation in the improved model is found to be smaller by a factor of 30 as compared to that obtained in our earlier paper. We also calculate the ionosphere dynamics with imposed zonal westward and eastward electric field based on SAMI3 code. It is found that the eastward (westward) electric field may trigger one (two) plasma bubble(s) in the nighttime ionosphere.

  13. Fiber optic probe having fibers with endfaces formed for improved coupling efficiency and method using same

    DOEpatents

    O'Rourke, Patrick E.; Livingston, Ronald R.

    1995-01-01

    A fiber optic probe for detecting scattered light, with transmitting and receiving fibers having slanted ends and bundled together to form a bevel within the tip of the probe. The probe comprises a housing with a transparent window across its tip for protecting the transmitting and receiving fibers held therein. The endfaces of the fibers are slanted, by cutting, polishing and the like, so that they lie in a plane that is not perpendicular to the longitudinal axis of the respective fiber. The fibers are held in the tip of the probe using an epoxy and oriented so that lines normal to the slanted endfaces are divergent with respect to one another. The epoxy, which is positioned substantially between the transmitting and receiving fibers, is tapered so that the transmitting fiber, the epoxy and the receiving fiber form a bevel of not more than 20 degrees. The angled fiber endfaces cause directing of the light cones toward each other, resulting in improved light coupling efficiency. A light absorber, such as carbon black, is contained in the epoxy to reduce crosstalk between the transmitting and receiving fibers.

  14. Fiber optic probe having fibers with endfaces formed for improved coupling efficiency and method using same

    DOEpatents

    O`Rourke, P.E.; Livingston, R.R.

    1995-03-28

    A fiber optic probe is disclosed for detecting scattered light, with transmitting and receiving fibers having slanted ends and bundled together to form a bevel within the tip of the probe. The probe comprises a housing with a transparent window across its tip for protecting the transmitting and receiving fibers held therein. The endfaces of the fibers are slanted, by cutting, polishing and the like, so that they lie in a plane that is not perpendicular to the longitudinal axis of the respective fiber. The fibers are held in the tip of the probe using an epoxy and oriented so that lines normal to the slanted endfaces are divergent with respect to one another. The epoxy, which is positioned substantially between the transmitting and receiving fibers, is tapered so that the transmitting fiber, the epoxy and the receiving fiber form a bevel of not more than 20 degrees. The angled fiber endfaces cause directing of the light cones toward each other, resulting in improved light coupling efficiency. A light absorber, such as carbon black, is contained in the epoxy to reduce crosstalk between the transmitting and receiving fibers. 3 figures.

  15. Improved single-cell culture achieved using micromolding in capillaries technology coupled with poly (HEMA)

    PubMed Central

    Ye, Fang; Jiang, Jin; Chang, Honglong; Xie, Li; Deng, Jinjun; Ma, Zhibo; Yuan, Weizheng

    2015-01-01

    Cell studies at the single-cell level are becoming more and more critical for understanding the complex biological processes. Here, we present an optimization study investigating the positioning of single cells using micromolding in capillaries technology coupled with the cytophobic biomaterial poly (2-hydroxyethyl methacrylate) (poly (HEMA)). As a cytophobic biomaterial, poly (HEMA) was used to inhibit cells, whereas the glass was used as the substrate to provide a cell adhesive background. The poly (HEMA) chemical barrier was obtained using micromolding in capillaries, and the microchannel networks used for capillarity were easily achieved by reversibly bonding the polydimethylsiloxane mold and the glass. Finally, discrete cell adhesion regions were presented on the glass surface. This method is facile and low cost, and the reagents are commercially available. We validated the cytophobic abilities of the poly (HEMA), optimized the channel parameters for higher quality and more stable poly (HEMA) patterns by investigating the effects of changing the aspect ratio and the width of the microchannel on the poly (HEMA) grid pattern, and improved the single-cell occupancy by optimizing the dimensions of the cell adhesion regions. PMID:26339307

  16. Improving sensitivity for microchip electrophoresis interfaced with inductively coupled plasma mass spectrometry using parallel multichannel separation.

    PubMed

    Cheng, Heyong; Liu, Jinhua; Xu, Zigang; Wang, Yuanchao; Ye, Meiying

    2016-08-26

    We reported sensitivity enhancement using multichannel parallel separation for microchip electrophoresis hyphenated with inductively coupled plasma mass spectrometry (MCE-ICP-MS) in this study. By using 2-20 array lanes for parallel separation, the sensitivity of the MCE-ICP-MS system was proportionally improved by 2-20 folds. No significantly adverse effect of parallel separation on column efficiency and resolution was observed. Rapid separation of Hg(2+) and methylmercuric (MeHg) ion within 36s under an electric field of 800Vcm(-1) was achieved in the 2-cm twenty-channels with a background electrolyte of 5mmolL(-1) borate buffer (pH 9.2). Detection limits of Hg(2+) and MeHg by the proposed system were decreased to 6.8-7.1ngL(-1). Good agreement between determined values and certified values of a certified reference fish was obtained with recoveries ranged between 94-98%. All results prove its advantages including high sensitivity, high efficiency and low operation cost, which are beneficial to routine analysis of metal speciation in environmental, biological and food fields. PMID:27488720

  17. Austin chalk maintains brisk drilling pace

    SciTech Connect

    Not Available

    1991-04-01

    Horizontal drilling in the Cretaceous Austin chalk trend of South Texas continues to set a fast pace. The Texas Railroad Commission has issued nearly 900 permits to drill horizontal wells in the Pearsall field area alone from 1984 through February 1991. TRC issued 1,485 permits for horizontal wells statewide during that period, including 1,285 since Jan. 1, 1990. Statewide, operators have reported completion of 685 horizontal wells. That includes 472 in Pearsall field, where TRC has issued 882 permits, and 121 in Giddings field, where 305 permits have been issued. Frio County, site of Pearsall field, led Texas counties with 494 permits and 278 horizontal completions. Oil drilling and reentry work is under way in many areas, and horizontal Austin chalk gas/condensate completions have been reported in Dimmit and Burleson counties.

  18. Accurate gradient approximation for complex interface problems in 3D by an improved coupling interface method

    NASA Astrophysics Data System (ADS)

    Shu, Yu-Chen; Chern, I.-Liang; Chang, Chien C.

    2014-10-01

    Most elliptic interface solvers become complicated for complex interface problems at those “exceptional points” where there are not enough neighboring interior points for high order interpolation. Such complication increases especially in three dimensions. Usually, the solvers are thus reduced to low order accuracy. In this paper, we classify these exceptional points and propose two recipes to maintain order of accuracy there, aiming at improving the previous coupling interface method [26]. Yet the idea is also applicable to other interface solvers. The main idea is to have at least first order approximations for second order derivatives at those exceptional points. Recipe 1 is to use the finite difference approximation for the second order derivatives at a nearby interior grid point, whenever this is possible. Recipe 2 is to flip domain signatures and introduce a ghost state so that a second-order method can be applied. This ghost state is a smooth extension of the solution at the exceptional point from the other side of the interface. The original state is recovered by a post-processing using nearby states and jump conditions. The choice of recipes is determined by a classification scheme of the exceptional points. The method renders the solution and its gradient uniformly second-order accurate in the entire computed domain. Numerical examples are provided to illustrate the second order accuracy of the presently proposed method in approximating the gradients of the original states for some complex interfaces which we had tested previous in two and three dimensions, and a real molecule (1D63) which is double-helix shape and composed of hundreds of atoms.

  19. Accurate gradient approximation for complex interface problems in 3D by an improved coupling interface method

    SciTech Connect

    Shu, Yu-Chen; Chern, I-Liang; Chang, Chien C.

    2014-10-15

    Most elliptic interface solvers become complicated for complex interface problems at those “exceptional points” where there are not enough neighboring interior points for high order interpolation. Such complication increases especially in three dimensions. Usually, the solvers are thus reduced to low order accuracy. In this paper, we classify these exceptional points and propose two recipes to maintain order of accuracy there, aiming at improving the previous coupling interface method [26]. Yet the idea is also applicable to other interface solvers. The main idea is to have at least first order approximations for second order derivatives at those exceptional points. Recipe 1 is to use the finite difference approximation for the second order derivatives at a nearby interior grid point, whenever this is possible. Recipe 2 is to flip domain signatures and introduce a ghost state so that a second-order method can be applied. This ghost state is a smooth extension of the solution at the exceptional point from the other side of the interface. The original state is recovered by a post-processing using nearby states and jump conditions. The choice of recipes is determined by a classification scheme of the exceptional points. The method renders the solution and its gradient uniformly second-order accurate in the entire computed domain. Numerical examples are provided to illustrate the second order accuracy of the presently proposed method in approximating the gradients of the original states for some complex interfaces which we had tested previous in two and three dimensions, and a real molecule ( (1D63)) which is double-helix shape and composed of hundreds of atoms.

  20. Prediction of Procrastination in a Self-Pacing Instructional System.

    ERIC Educational Resources Information Center

    Ely, Donald D.; Hampton, John D.

    The objective of the study was to predict potential procrastinators in a self-pacing instructional system. Seventy-five entering college freshmen were randomly selected to participate in a large scale individually-paced program. Those students (25) who procrastinated were classified as "no-start-procrastinators" (NSP); the remainder (52) were…

  1. Rural Policy Development: An NRHA and PACE Association Collaborative Model

    ERIC Educational Resources Information Center

    Fitzgerald, Peter; Morgan, Alan; Morris, Tom

    2004-01-01

    The Program of All-Inclusive Care for the Elderly (PACE) offers a unique model of comprehensive care for frail, elderly people. To date, all of the PACE programs have been located in urban areas. Rural advocates and policymakers, however, believe the program may hold great promise for use in rural areas, which have higher percentages of elderly…

  2. Less Is More: Pacing in the ESL Class.

    ERIC Educational Resources Information Center

    Shaunnessey, Maryann S.

    Pacing in the teaching of English as a second language (ESL) is considered. It is suggested that the problem of pacing is almost entirely a matter of teachers covering material so rapidly that the student frequently does not have the opportunity to integrate it. Since the recognition of sounds, symbols, and sentences is not mastery of them, it is…

  3. Achievement Monitoring of Individually Paced Instruction. Final Report.

    ERIC Educational Resources Information Center

    Pinsky, Paul D.

    A study was made to monitor achievement of individually paced instruction. The project concentrated on designing testing procedures in group paced instructional programs to provide information to student, teachers, parents and administrators which could be used in both a formative and summative evaluation. The three objectives of the project were:…

  4. Social Interaction in Self-Paced Distance Education

    ERIC Educational Resources Information Center

    Anderson, Terry; Upton, Lorne; Dron, Jon; Malone, Judi; Poelhuber, Bruno

    2015-01-01

    In this paper we present a case study of a self-paced university course that was originally designed to support independent, self-paced study at distance. We developed a social media intervention, in design-based research terms, that allows these independent students to contribute archived content to enhance the course, to engage in discussions…

  5. Is Self-Paced Instruction Really Worth It?

    ERIC Educational Resources Information Center

    Roberson, J. A.; Crowe, C. T.

    1975-01-01

    Describes a self-paced, learning-for-mastery course in undergraduate fluid mechanics. Includes the method of course assessment, method of student evaluation, and a description of the instructor's role and work load. Summarizes aspects of self-paced instruction considered favorable and unfavorable. (GS)

  6. Accelerating the "Pace" against Illiteracy: Parent and Child Education.

    ERIC Educational Resources Information Center

    Noe, Roger

    1989-01-01

    In 1980, Kentucky reported the nation's lowest percentage of adults, aged 25 and older, who had graduated from high school. Legislators were inundated with recommendations for reform. The result was the enactment of the Parent and Child Education (PACE) pilot program (1986). In the PACE program, parents without high school diplomas attend classes…

  7. Together - a couples' program to improve communication, coping, and financial management skills: development and initial pilot-testing.

    PubMed

    Falconier, Mariana K

    2015-04-01

    The accumulated knowledge about the negative impact of financial strain on couple's relationship functioning and the magnitude of the latest economic downturn have brought together the fields of financial counseling and couples' therapy. This article describes the development of a new interdisciplinary program that aims at helping couples under financial strain improve their financial management, communication, and dyadic coping skills. The article also reports the results from its initial pilot-testing with data collected from 18 financially distressed couples before and after participation in the program and 3 months later. Results from repeated measures ANOVAs suggest that the program may help reduce both partners' financial strain and the male negative communication and improve both partners' financial management skills and strategies to cope together with financial strain, and the male relationship satisfaction. These findings together with the high satisfaction reported by participants regarding the structure and content of the sessions and homework suggest that this program may be a promising approach to help couples experiencing financial strain. Gender differences, clinical implications, and possibilities for further research are also discussed. PMID:24910157

  8. Right Bundle Branch Block-Like Pattern During Uncomplicated Right Ventricular Pacing and the Effect of Pacing Site.

    PubMed

    Tzeis, Stylianos; Andrikopoulos, George; Weigand, Severin; Grebmer, Christian; Semmler, Verena; Brkic, Amir; Asbach, Stefan; Kloppe, Axel; Lennerz, Carsten; Bourier, Felix; Pastromas, Sokratis; Kolb, Christof

    2016-03-15

    Right bundle branch block (RBBB) configuration is an unexpected finding during right ventricular (RV) pacing that raises the suspicion of inadvertent left ventricular lead positioning. The aim of this study was to evaluate the prevalence of paced RBBB pattern in relation to RV lead location. This is a secondary analysis of a prospective, multicenter study, which randomized implantable cardioverter defibrillator recipients to an apical versus midseptal defibrillator lead positioning. A 12-lead electrocardiogram was recorded during intrinsic rhythm and RV pacing. Paced RBBB-like pattern was defined as positive (>0.05 mV) net amplitude of QRS complex in leads V1 and/or V2. In total, 226 patients (65.6 ± 12.0 years, 20.8% women, 53.1% apical site) were included in the study. The prevalence of paced RBBB pattern in the total population was 15.5%. A significantly lower percentage of patients in the midseptal group demonstrated RBBB-type configuration during RV pacing compared with the apical group (1.9% vs 27.5%, p <0.001). Baseline RBBB, prolonged QRS duration during intrinsic rhythm, and reduced ejection fraction were not associated with increased likelihood of paced RBBB. In the subgroup of patients with RBBB type during pacing, 91.4% of patients had a paced QRS axis from -30° to -90°, whereas 100% of patients displayed a negative QRS vector at lead V3. In conclusion, RBBB configuration is encountered in a considerable percentage of device recipients during uncomplicated RV pacing. Midseptal lead positioning is associated with significantly lower likelihood of paced RBBB pattern compared with apical location. PMID:26796192

  9. Selective pulmonary vasodilation improves ventriculovascular coupling and gas exchange in a patient with unrepaired single-ventricle physiology.

    PubMed

    Rischard, F; Vanderpool, R; Jenkins, I; Dalabih, M; Colombo, J; Lax, D; Seckeler, M

    2015-06-01

    We describe a 63-year-old patient with unrepaired tricuspid valve atresia and a hypoplastic right ventricle (single-ventricle physiology) who presented with progressive symptomatic hypoxia. Her anatomy resulted in parallel pulmonary and systemic circulations, pulmonary arterial hypertension, and uncoupling of the ventricle/pulmonary artery. Hemodynamic and coupling data were obtained before and after pulmonary vasoactive treatment, first inhaled nitric oxide and later inhaled treprostinil. The coupling ratio (ratio of ventricular to vascular elastance) shunt fractions and dead space ventilation were calculated before and after treatment. Treatment resulted in improvement of the coupling ratio between the ventricle and the vasculature with optimization of stroke work, equalization of pulmonary and systolic flows, a decrease in dead space ventilation from 75% to 55%, and a significant increase in 6-minute walk distance and improved hypoxia. Inhaled treprostinil significantly increased 6-minute walk distance and improved hypoxia. This is the first report to show that pulmonary vasoactive treatment can be used in a patient with unrepaired single-ventricle anatomy and describes the hemodynamic effects of inhaled therapy on ventriculovascular coupling and gas exchange in the pulmonary circulation in this unique physiology. PMID:26064468

  10. Improved sphaleron decoupling condition and the Higgs coupling constants in the real singlet-extended standard model

    NASA Astrophysics Data System (ADS)

    Fuyuto, Kaori; Senaha, Eibun

    2014-07-01

    We improve the sphaleron decoupling condition in the real singlet-extended standard model (SM). The sphaleron energy is obtained using the finite-temperature one-loop effective potential with daisy resummation. For moderate values of the model parameters, the sphaleron decoupling condition is found to be vC/TC>(1.1-1.2), where TC denotes a critical temperature and vC is the corresponding vacuum expectation value of the doublet Higgs field at TC. We also investigate the deviation of the triple Higgs boson coupling from its standard model value in the region where the improved sphaleron decoupling condition is satisfied. As a result of the improvement, the deviation of the triple Higgs boson coupling gets more enhanced. In a typical case, if the Higgs couplings to the gauge bosons/fermions deviate from the SM values by about 3 (10)%, the deviation of the triple Higgs boson coupling can be as large as about 16 (50)%, which is about 4 (8)% larger than that based on the conventional criterion vC/TC>1.

  11. Improvement of the directional stability of passenger car trailer couplings with actively controlled steering

    NASA Astrophysics Data System (ADS)

    Desens, Jens

    The stabilization of pendulum oscillations of passenger car trailer couplings, using active steering, was examined. A linear model of the couplings was presented. Each axle was provided with a controller. The controllers were optimized, with regard to necessary sensors, in order to minimize costs. The rear and the front axles were provided with a control unit in order to compute the potential prevailing in the active steering of several axles. It was shown that the passenger car rear axle was the most suitable for coupling stabilization. The experiment was simulated, using a complex coupling model. The developed controller allowed the passenger car trailer to be driven at a speed higher than 150 km per hour.

  12. Distant electric coupling between nitrate reduction and sulphide oxidation investigated by an improved nitrate microscale biosensor

    NASA Astrophysics Data System (ADS)

    Marzocchi, U.; Revsbech, N. P.; Nielsen, L. P.; Risgaard-Petersen, N.

    2012-04-01

    Bacteria are apparently able to transmit electrons to other bacteria (Summers et al. 2010) or to electrodes (Malvankar et al. 2011) by some kind of nanowires (Reguera et al. 2005, Gorbi et al. 2006). Lately it has been shown that such transfer may occur over distances of centimetres in sediments, thereby coupling sulphide oxidation in deeper layers with oxygen reduction near the surface (Nielsen 2011). The finding of these long-distance electrical connections originated from analysis of O2, H2S, and pH profiles measured with microsensors. Nitrate is thermodynamically almost as good an electron acceptor as O2, and we therefore set up an experiment to investigate whether long-distance electron transfer also happens with NO3-. Aquaria were filled with sulphidic marine sediment from Aarhus Bay that was previously used to show long-distance electron transfer to O2. The aquaria were equipped with a lid so that they could be completely filled without a gas phase. Anoxic seawater with 300 μM NO3- was supplied at a constant rate resulting in a steady state concentration in the aquatic phase of 250 μM NO3-. The reservoir with the nitrate-containing water was kept anoxic by bubbling it with a N2/CO2 mixture and was kept at an elevated temperature. The water was cooled on the way to the aquaria to keep the water in the aquaria undersaturated with gasses, so that bubble formation by denitrification in the sediment could be minimised. Profiles of NO3-, H2S, and pH were measured as a function of time (2 months) applying commercial sensors for H2S and pH and an improved microscale NO3- biosensor developed in our laboratory. The penetration of NO3- in the sediment was 4-5 mm after 2 months, whereas sulphide only could be detected below 8-9 mm depth. The electron acceptor and electron donor were thus separated by 4-5 mm, indicating long distance electron transfer. A pH maximum of about 8.6 pH units at the NO3- reduction zone similar to a pH maximum observed in the O2 reduction

  13. An improved coupling design for high-frequency TE011 electron paramagnetic resonance cavities

    NASA Astrophysics Data System (ADS)

    Savitsky, A.; Grishin, Yu.; Rakhmatullin, R.; Reijerse, E.; Lubitz, W.

    2013-01-01

    In high-frequency electron paramagnetic resonance (EPR) spectroscopy the sample is usually accommodated in a single-mode cylindrical TE011 microwave cavity. This cavity stands out in terms of flexibility for various types of EPR experiments due to convenient control of its resonance frequency and easy waveguide-to-cavity microwave coupling. In continuous wave and in pulsed EPR it is, however, essential to be able to vary the coupling efficiency over a large range. We present a new mechanical design to vary the microwave coupling to the cavity using a movable metal sphere. This coupling sphere is shifted in the plane of the iris wall inside the coupling waveguide. The design allows for a compact and robust construction of the EPR probehead that can be easily accommodated inside a limited space of helium flow cryostat. The construction details and characterization of the coupling element for 95 GHz (W-band) EPR as well as for 34 GHz (Q-band) are presented.

  14. Computer-Paced versus Experimenter-Paced Working Memory Span Tasks: Are They Equally Reliable and Valid?

    ERIC Educational Resources Information Center

    Bailey, Heather

    2012-01-01

    Working memory span tasks are popular measures, in part, because performance on these tasks predicts performance on other measures of cognitive ability. The traditional method of span-task administration is the experimenter-paced version, whose reliability and validity have been repeatedly demonstrated. However, computer-paced span tasks are…

  15. Pushing the pace of tree species migration.

    PubMed

    Lazarus, Eli D; McGill, Brian J

    2014-01-01

    Plants and animals have responded to past climate changes by migrating with habitable environments, sometimes shifting the boundaries of their geographic ranges by tens of kilometers per year or more. Species migrating in response to present climate conditions, however, must contend with landscapes fragmented by anthropogenic disturbance. We consider this problem in the context of wind-dispersed tree species. Mechanisms of long-distance seed dispersal make these species capable of rapid migration rates. Models of species-front migration suggest that even tree species with the capacity for long-distance dispersal will be unable to keep pace with future spatial changes in temperature gradients, exclusive of habitat fragmentation effects. Here we present a numerical model that captures the salient dynamics of migration by long-distance dispersal for a generic tree species. We then use the model to explore the possible effects of assisted colonization within a fragmented landscape under a simulated tree-planting scheme. Our results suggest that an assisted-colonization program could accelerate species-front migration rates enough to match the speed of climate change, but such a program would involve an environmental-sustainability intervention at a massive scale. PMID:25162663

  16. Pushing the Pace of Tree Species Migration

    PubMed Central

    Lazarus, Eli D.; McGill, Brian J.

    2014-01-01

    Plants and animals have responded to past climate changes by migrating with habitable environments, sometimes shifting the boundaries of their geographic ranges by tens of kilometers per year or more. Species migrating in response to present climate conditions, however, must contend with landscapes fragmented by anthropogenic disturbance. We consider this problem in the context of wind-dispersed tree species. Mechanisms of long-distance seed dispersal make these species capable of rapid migration rates. Models of species-front migration suggest that even tree species with the capacity for long-distance dispersal will be unable to keep pace with future spatial changes in temperature gradients, exclusive of habitat fragmentation effects. Here we present a numerical model that captures the salient dynamics of migration by long-distance dispersal for a generic tree species. We then use the model to explore the possible effects of assisted colonization within a fragmented landscape under a simulated tree-planting scheme. Our results suggest that an assisted-colonization program could accelerate species-front migration rates enough to match the speed of climate change, but such a program would involve an environmental-sustainability intervention at a massive scale. PMID:25162663

  17. Coupling of Helmholtz resonators to improve acoustic liners for turbofan engines at low frequency

    NASA Technical Reports Server (NTRS)

    Dean, L. W.

    1975-01-01

    An analytical and test program was conducted to evaluate means for increasing the effectiveness of low frequency sound absorbing liners for aircraft turbine engines. Three schemes for coupling low frequency absorber elements were considered. These schemes were analytically modeled and their impedance was predicted over a frequency range of 50 to 1,000 Hz. An optimum and two off-optimum designs of the most promising, a parallel coupled scheme, were fabricated and tested in a flow duct facility. Impedance measurements were in good agreement with predicted values and validated the procedure used to transform modeled parameters to hardware designs. Measurements of attenuation for panels of coupled resonators were consistent with predictions based on measured impedance. All coupled resonator panels tested showed an increase in peak attenuation of about 50% and an increase in attenuation bandwidth of one one-third octave band over that measured for an uncoupled panel. These attenuation characteristics equate to about 35% greater reduction in source perceived noise level (PNL), relative to the uncoupled panel, or a reduction in treatment length of about 24% for constant PNL reduction. The increased effectiveness of the coupled resonator concept for attenuation of low frequency broad spectrum noise is demonstrated.

  18. DOA Estimation under Unknown Mutual Coupling and Multipath with Improved Effective Array Aperture.

    PubMed

    Wang, Yuexian; Trinkle, Matthew; Ng, Brian W-H

    2015-01-01

    Subspace-based high-resolution direction of arrival (DOA) estimation significantly deteriorates under array manifold perturbation and rank deficiency of the covariance matrix due to mutual coupling and multipath propagation, respectively. In this correspondence, the unknown mutual coupling can be circumvented by the proposed method without any passive or active calibration process, and the DOA of the coherent signals can be accurately estimated accordingly. With a newly constructed matrix, the deficient rank can be restored, and the effective array aperture can be extended compared with conventional spatial smoothing. The proposed method achieves a good robustness and DOA estimation accuracy with unknown mutual coupling. The simulation results demonstrate the validity and efficiency of the proposed method. PMID:26670235

  19. Use of external magnetic fields in hohlraum plasmas to improve laser-coupling

    SciTech Connect

    Montgomery, D. S. Albright, B. J.; Kline, J. L.; Yin, L.; Barnak, D. H.; Chang, P. Y.; Davies, J. R.; Fiksel, G.; Froula, D. H.; Betti, R.; MacDonald, M. J.; Sefkow, A. B.

    2015-01-15

    Efficient coupling of laser energy into hohlraum targets is important for indirect drive ignition. Laser-plasma instabilities can reduce coupling, reduce symmetry, and cause preheat. We consider the effects of an external magnetic field on laser-energy coupling in hohlraum targets. Experiments were performed at the Omega Laser Facility using low-Z gas-filled hohlraum targets which were placed in a magnetic coil with B{sub z} ≤ 7.5-T. We found that an external field B{sub z} = 7.5-T aligned along the hohlraum axis results in up to a 50% increase in plasma temperature as measured by Thomson scattering. The experiments were modeled using the 2-D magnetohydrodynamics package in HYDRA and were found to be in good agreement.

  20. Use of external magnetic fields in hohlraum plasmas to improve laser-coupling

    NASA Astrophysics Data System (ADS)

    Montgomery, D. S.; Albright, B. J.; Barnak, D. H.; Chang, P. Y.; Davies, J. R.; Fiksel, G.; Froula, D. H.; Kline, J. L.; MacDonald, M. J.; Sefkow, A. B.; Yin, L.; Betti, R.

    2015-01-01

    Efficient coupling of laser energy into hohlraum targets is important for indirect drive ignition. Laser-plasma instabilities can reduce coupling, reduce symmetry, and cause preheat. We consider the effects of an external magnetic field on laser-energy coupling in hohlraum targets. Experiments were performed at the Omega Laser Facility using low-Z gas-filled hohlraum targets which were placed in a magnetic coil with Bz ≤ 7.5-T. We found that an external field Bz = 7.5-T aligned along the hohlraum axis results in up to a 50% increase in plasma temperature as measured by Thomson scattering. The experiments were modeled using the 2-D magnetohydrodynamics package in HYDRA and were found to be in good agreement.

  1. Use of external magnetic fields in hohlraum plasmas to improve laser-coupling

    DOE PAGESBeta

    Montgomery, D. S.; Albright, B. J.; Barnak, D. H.; Chang, P. Y.; Davies, J. R.; Fiksel, G.; Froula, D. H.; Kline, J. L.; MacDonald, M. J.; Sefkow, A. B.; et al

    2015-01-13

    Efficient coupling of laser energy into hohlraum targets is important for indirect drive ignition. Laser-plasma instabilities can reduce coupling, reduce symmetry, and cause preheat. We consider the effects of an external magnetic field on laser-energy coupling in hohlraum targets. Experiments were performed at the Omega Laser Facility using low-Z gas-filled hohlraum targets which were placed in a magnetic coil with Bz ≤ 7.5-T. We found that an external field Bz = 7.5-T aligned along the hohlraum axis results in up to a 50% increase in plasma temperature as measured by Thomson scattering. As a result, the experiments were modeled usingmore » the 2-D magnetohydrodynamics package in HYDRA and were found to be in good agreement.« less

  2. Use of external magnetic fields in hohlraum plasmas to improve laser-coupling

    SciTech Connect

    Montgomery, D. S.; Albright, B. J.; Barnak, D. H.; Chang, P. Y.; Davies, J. R.; Fiksel, G.; Froula, D. H.; Kline, J. L.; MacDonald, M. J.; Sefkow, A. B.; Yin, L.; Betti, R.

    2015-01-13

    Efficient coupling of laser energy into hohlraum targets is important for indirect drive ignition. Laser-plasma instabilities can reduce coupling, reduce symmetry, and cause preheat. We consider the effects of an external magnetic field on laser-energy coupling in hohlraum targets. Experiments were performed at the Omega Laser Facility using low-Z gas-filled hohlraum targets which were placed in a magnetic coil with Bz ≤ 7.5-T. We found that an external field Bz = 7.5-T aligned along the hohlraum axis results in up to a 50% increase in plasma temperature as measured by Thomson scattering. As a result, the experiments were modeled using the 2-D magnetohydrodynamics package in HYDRA and were found to be in good agreement.

  3. DOA Estimation under Unknown Mutual Coupling and Multipath with Improved Effective Array Aperture

    PubMed Central

    Wang, Yuexian; Trinkle, Matthew; Ng, Brian W.-H.

    2015-01-01

    Subspace-based high-resolution direction of arrival (DOA) estimation significantly deteriorates under array manifold perturbation and rank deficiency of the covariance matrix due to mutual coupling and multipath propagation, respectively. In this correspondence, the unknown mutual coupling can be circumvented by the proposed method without any passive or active calibration process, and the DOA of the coherent signals can be accurately estimated accordingly. With a newly constructed matrix, the deficient rank can be restored, and the effective array aperture can be extended compared with conventional spatial smoothing. The proposed method achieves a good robustness and DOA estimation accuracy with unknown mutual coupling. The simulation results demonstrate the validity and efficiency of the proposed method. PMID:26670235

  4. Improved extraction of hydrologic information from geophysical data through coupled hydrogeophysical inversion

    SciTech Connect

    Hinnell, A.C.; Ferre, T.P.A.; Vrugt, J.A.; Huisman, J.A.; Moysey, S.; Rings, J.; Kowalsky, M.B.

    2009-11-01

    There is increasing interest in the use of multiple measurement types, including indirect (geophysical) methods, to constrain hydrologic interpretations. To date, most examples integrating geophysical measurements in hydrology have followed a three-step, uncoupled inverse approach. This approach begins with independent geophysical inversion to infer the spatial and/or temporal distribution of a geophysical property (e.g. electrical conductivity). The geophysical property is then converted to a hydrologic property (e.g. water content) through a petrophysical relation. The inferred hydrologic property is then used either independently or together with direct hydrologic observations to constrain a hydrologic inversion. We present an alternative approach, coupled inversion, which relies on direct coupling of hydrologic models and geophysical models during inversion. We compare the abilities of coupled and uncoupled inversion using a synthetic example where surface-based electrical conductivity surveys are used to monitor one-dimensional infiltration and redistribution.

  5. 42 CFR 460.24 - Limit on number of PACE program agreements.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... SERVICES (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PACE Organization Application and Waiver Process § 460.24 Limit on number...

  6. 42 CFR 460.24 - Limit on number of PACE program agreements.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... SERVICES (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PACE Organization Application and Waiver Process § 460.24 Limit on number...

  7. 42 CFR 460.24 - Limit on number of PACE program agreements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... SERVICES (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PACE Organization Application and Waiver Process § 460.24 Limit on number...

  8. 42 CFR 460.24 - Limit on number of PACE program agreements.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... SERVICES (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PACE Organization Application and Waiver Process § 460.24 Limit on number...

  9. 42 CFR 460.24 - Limit on number of PACE program agreements.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... SERVICES (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PACE Organization Application and Waiver Process § 460.24 Limit on number...

  10. Improved field stability in RFQ structures with vane-coupling rings

    SciTech Connect

    Schneider, H.R.; Lancaster, H.

    1983-03-01

    The small apertures common in many RFQ linac designs lead to tuning difficulties, primarily because asymmetries in the quadrant fields can arise as a result of small non-uniformities in the vane-to-vane capacitances. Sensitivity to such capacitance or other tuning variation in the quadrants is greatly reduced by the introduction of pairs of vane-coupling rings that provide periodic electrical connections between diametrically opposite vanes. Results of measurements on a cold model RFQ structure with and without vane-coupling rings are presented. The number of rings required for field stabilization and the effect of rings on mode frequencies are discussed.

  11. Remote Sensing Ocean Color Observations from NASA's PACE Mission: Applications and Societal Benefits

    NASA Astrophysics Data System (ADS)

    Tzortziou, M.; Omar, A. H.; Turner, W.

    2014-12-01

    The PACE (Pre- Aerosol, Clouds and ocean Ecosystems) mission is a strategic Climate Continuity mission, included in NASA's 2010 plan: "Responding to the Challenge of Climate and Environmental Change: NASA's Plan for a Climate-Centric Architecture for Earth Observations and Applications from Space". On a polar orbit, PACE will make climate-quality global measurements that are essential for understanding ocean biology, biogeochemistry and ecology, and determining how the ocean's role in global biogeochemical cycling and ocean ecology both affects and is affected by climate change. With advanced global remote sensing capabilities that include high spectral-resolution imaging, extended spectral coverage to the UV and SWIR, improved spatial resolution in inland, estuarine and coastal waters, enhanced atmospheric correction and higher signal-to-noise, PACE is expected to provide high quality observations that, over the long-term, will contribute to an extended time series of records on inland, coastal, and ocean ecosystems—all of which have substantial value beyond basic science and research. The combination of climate-quality, global atmospheric and oceanic observations provided by the PACE mission will provide a unique capability to help understand changes that affect our ecosystem services, implement science-based management strategies of coastal, marine and inland aquatic resources, and support assessments, policy analyses, and design approaches to plan adaptation and responses to impacts of climate change. Here we discuss the PACE applications program, the new capabilities afforded by this future satellite mission, and how they could potentially advance applications across a range of areas, including Oceans, Climate, Water Resources, Ecological Forecasting, Disasters, Human Health and Air Quality.

  12. Self-Paced Timing Detects and Tracks Change in Prodromal Huntington Disease

    PubMed Central

    Rowe, Kelly C.; Paulsen, Jane S.; Langbehn, Douglas R.; Duff, Kevin; Beglinger, Leigh J.; Wang, Chiachi; O’Rourke, Justin J.F.; Stout, Julie C.; Moser, David J.

    2010-01-01

    Objective This study compares self-paced timing performance (cross-sectionally and longitudinally) between participants with prodromal Huntington disease (pr-HD) and a comparison group of gene non-expanded participants from affected families (NC). Methods At baseline, participants in two groups (747 pr-HD: 188 NC) listened to tones presented at 550ms intervals, matched that pace by tapping response keys and continued the rhythm (self-paced) after the tone had stopped. Standardized cross-sectional and longitudinal linear models examined the relationships between self-paced timing precision and estimated proximity to diagnosis, and various other demographic factors. Results Pr-HD participants showed significantly less timing precision than NC. Cross-sectional comparison of pr-HD and NC participants showed a significant performance difference on two administration conditions of the task (dominant hand: p<.0001; alternating thumbs: p<.0001). Additionally, estimated proximity to diagnosis was related to timing precision in both conditions, (dominant hand: t=−11.14,df=920, p<.0001; alternating thumbs: t=−11.32, df=918, p<.0001), even considering demographic and experience variables. Longitudinal modeling showed that pr-HD participants worsen more quickly at the task than the NC group, and that decline rate increases with estimated proximity to diagnosis in both conditions (dominant hand: t=−2.85,df=417, p=.0045; alternating thumbs: t=−3.56, df= 445, p=.0004). Effect sizes based on adjusted mean annual change ranged from −0.34 to 0.25 in the longitudinal model. Conclusions The self-paced timing paradigm has potential for use as a screening tool and outcome measure in pr-HD clinical trials to gauge therapeutically-mediated improvement or maintenance of function. PMID:20604618

  13. Improving the sensitivity of J coupling measurements in solids with application to disordered materials

    NASA Astrophysics Data System (ADS)

    Guerry, Paul; Brown, Steven P.; Smith, Mark E.

    2016-05-01

    It has been shown previously that for magic angle spinning (MAS) solid state NMR the refocused INADEQUATE spin-echo (REINE) experiment can usefully quantify scalar (J) couplings in disordered solids. This paper focuses on the two z filter components in the original REINE pulse sequence, and investigates by means of a product operator analysis and fits to density matrix simulations the effects that their removal has on the sensitivity of the experiment and on the accuracy of the extracted J couplings. The first z filter proves unnecessary in all the cases investigated here and removing it increases the sensitivity of the experiment by a factor ˜1.1-2.0. Furthermore, for systems with broad isotropic chemical shift distributions (namely whose full widths at half maximum are greater than 30 times the mean J coupling strength), the second z filter can also be removed, thus allowing whole-echo acquisition and providing an additional √2 gain in sensitivity. Considering both random and systematic errors in the values obtained, J couplings determined by fitting the intensity modulations of REINE experiments carry an uncertainty of 0.2-1.0 Hz (˜1-10 %).

  14. Application of Phase Smoothing Pseudo Range PPP/INS Tightly Coupled Technique in Improving the Results of Low Precision MEMS

    NASA Astrophysics Data System (ADS)

    Luo, X.

    2015-12-01

    In land surveying and engineering surveying, we need to obtain high precision navigation results. However, due to the inertial device costs less than a introduction, commonly used low precision inertial navigation equipment with tightly coupled GPS / INS integrated to get high precision navigation results. Many studies have improved the accuracy of error by using the UKF and CKF filtering algorithm, but it is still using the traditional pseudo code directly, the improvement effect is not obvious, and the disturbance is large. In this study, the PPP /INSmodel is improved by using the carrier phase smoothing pseudo range algorithm. Experimental results show that based on phase smoothing pseudo range PPP/INS tight coupled method, the position precision and the velocity precision for of the measured data of higher accuracy of MEMS and GPS receiver can get to a decimeter level and centimeter level. This coupling method has higher accuracy, stronger anti disturbance and Have a better convergence than the traditional C/A code. Based on different phase smoothing epoch number combination the accuracy and smoothing effect is also different, the larger smooth epoch number is, the better treatment effect it has and The higher precision it has. For high precision measurement, the equipment cost is saved. It has a practical significance meaning in the measurement of outdoor ground.

  15. Improving picogram mass sensitivity via frequency doubling in coupled silicon micro-cantilevers

    NASA Astrophysics Data System (ADS)

    Wang, Dong F.; Du, Xu; Wang, Xin; Ikehara, Tsuyoshi; Maeda, Ryutaro

    2016-01-01

    Two geometrically different cantilevers, with primary frequencies of 182.506 kHz (u-shaped cantilever for sensing) and 372.503 kHz (rectangular cantilever for detecting), were coupled by two symmetrical coupling overhangs for oscillation-based mass sensing verification with phase-locking. Based on a lumped element model, a theoretical expression, containing a nonlinear spring constant and a term corresponding to the effect of the coupling spring, was proposed to consider the factors influencing the entrainment range, which is defined as a plateau with a frequency ratio (resonant frequency of rectangular cantilever to that of u-shaped cantilever) of 2.000 in present study. A picogram order mass sensing by applying a polystyrene microsphere as a small mass perturbation onto the tip of the u-shaped cantilever was demonstrated. By varying driving voltages, two entrainment regions with and without microsphere were experimentally measured and comparatively shown. At a driving voltage of 1 Vpp, when the u-shaped cantilever was excited at its shifted frequency of 180.29 kHz, the frequency response of the coupled rectangular cantilever had a peak at double the shifted frequency of 360.58 kHz of the u-shaped cantilever. The frequency shift for picogram mass sensing was thus doubled from 2560 Hz to 5133 Hz due to phase-locking. A mass of 3.732 picogram was derived based on the doubled frequency shift corresponding to a calculated mass of 3.771 picogram from measured diameter and reported density. Both experimental demonstration and theoretical discussions from the viewpoint of entrainment range elicits the possibility of increasing the mass sensitivity via phase-locking in the coupled silicon micro-cantilevers.

  16. Fast Paced, Low Cost Projects at MSFC

    NASA Technical Reports Server (NTRS)

    Watson-Morgan, Lisa; Clinton, Raymond

    2012-01-01

    What does an orbiting microsatellite, a robotic lander and a ruggedized camera and telescope have in common? They are all fast paced, low cost projects managed by Marshall Space Flight Center (MSFC) teamed with successful industry partners. MSFC has long been synonymous with human space flight large propulsion programs, engineering acumen and risk intolerance. However, there is a growing portfolio/product line within MSFC that focuses on these smaller, fast paced projects. While launching anything into space is expensive, using a managed risk posture, holding to schedule and keeping costs low by stopping at egood enough f were key elements to their success. Risk is defined as the possibility of loss or failure per Merriam Webster. The National Aeronautics and Space Administration (NASA) defines risk using procedural requirement 8705.4 and establishes eclasses f to discern the acceptable risk per a project. It states a Class D risk has a medium to significant risk of not achieving mission success. MSFC, along with industry partners, has created a niche in Class D efforts. How did the big, cautious MSFC succeed on these projects that embodied the antithesis of its heritage in human space flight? A key factor toward these successful projects was innovative industry partners such as Dynetics Corporation, University of Alabama in Huntsville (UAHuntsville), Johns Hopkins Applied Physics Laboratory (JHU APL), Teledyne Brown Engineering (TBE), Von Braun Center for Science and Innovation (VCSI), SAIC, and Jacobs. Fast Affordable Satellite Technology (FastSat HSV01) is a low earth orbit microsatellite that houses six instruments with the primary scientific objective of earth observation and technology demonstration. The team was comprised of Dynetics, UAHuntsvile, SAIC, Goddard Space Flight Center (GSFC) and VCSI with the United States Air Force Space Test Program as the customer. The team completed design, development, manufacturing, environmental test and integration in

  17. Improved simulation of tropospheric ozone by a global-multi-regional two-way coupling model system

    NASA Astrophysics Data System (ADS)

    Yan, Yingying; Lin, Jintai; Chen, Jinxuan; Hu, Lu

    2016-02-01

    from 0.53 to 0.68, and it reduces the mean model bias from 10.8 to 6.7 ppb. Regionally, the coupled system reduces the bias by 4.6 ppb over Europe, 3.9 ppb over North America and 3.1 ppb over other regions. The two-way coupling brings O3 vertical profiles much closer to the HIPPO (for remote areas) and MOZAIC (for polluted regions) data, reducing the tropospheric (0-9 km) mean bias by 3-10 ppb at most MOZAIC sites and by 5.3 ppb for HIPPO profiles. The two-way coupled simulation also reduces the global tropospheric column ozone by 3.0 DU (9.5 %, annual mean), bringing them closer to the OMI data in all seasons. Additionally, the two-way coupled simulation also reduces the global tropospheric mean hydroxyl radical by 5 % with improved estimates of methyl chloroform and methane lifetimes. Simulation improvements are more significant in the Northern Hemisphere, and are mainly driven by improved representation of spatial inhomogeneity in chemistry/emissions. Within the nested domains, the two-way coupled simulation reduces surface ozone biases relative to typical GEOS-Chem one-way nested simulations, due to much improved LBCs. The bias reduction is 1-7 times the bias reduction from the global to the one-way nested simulation. Improving model representations of small-scale processes is important for understanding the global and regional tropospheric chemistry.

  18. Ultra-wide bandwidth improvement of piezoelectric energy harvesters through electrical inductance coupling

    NASA Astrophysics Data System (ADS)

    Abdelmoula, H.; Abdelkefi, A.

    2015-11-01

    The design and analysis of innovative ultra-wide bandwidth piezoelectric energy harvesters are deeply investigated. An electrical inductance is considered in the harvester's circuit to be connected in series or parallel to a load resistance. A lumped-parameter model is used to model the electromechanical response of the harvester when subjected to harmonic excitations. A linear comprehensive analysis is performed to investigate the effects of an electrical inductance on the coupled frequencies and damping of the harvester. It is shown that including an electrical inductance connected in series or in parallel to an electrical load resistance can result in the appearance of a second coupled frequency of electrical type. The results show that the inclusion of an inductance may give the opportunity to tune one of the coupled frequencies of mechanical and electrical types to the available excitation frequency in the environment. Using the gradient method, an optimization analysis is then performed to determine the optimum values of the electrical inductance and load resistance that maximize the harvested power. It is demonstrated that, for each excitation frequency, there is a combination of optimum values of the electrical inductance and resistance in such a way an optimum constant value of the harvested power is found. Numerical analysis is then performed to show the importance of considering an additional inductance in the harvester's circuitry in order to design broadband energy harvesters. The results show that the presence of the second coupled frequency of electrical type due to the inductance gives the possibility to design optimal broadband inductive-resistive piezoelectric energy harvesters with minimum displacement due to shunt damping effect.

  19. Improving the Mass-Limited Performance of Routine NMR Probes using Coupled Coils.

    PubMed

    Marsden, Brian; Lim, Victor; Taber, Bob; Zens, Albert

    2016-07-01

    We report a method to convert, on demand, a general use dual-broadband probe to a high performance mass-limited probe for both high band and low band nuclei. This technology uses magnetic coupling of inductors to achieve this capability. The method offers a cost effective way of increasing the performance of routine NMR probes without having to change probes or increase the overall foot print of the spectrometer. PMID:27155588

  20. G protein-coupled receptors: signalling and regulation by lipid agonists for improved glucose homoeostasis.

    PubMed

    Moran, Brian M; Flatt, Peter R; McKillop, Aine M

    2016-04-01

    G protein-coupled receptors (GPCRs) play a pivotal role in cell signalling, controlling many processes such as immunity, growth, cellular differentiation, neurological pathways and hormone secretions. Fatty acid agonists are increasingly recognised as having a key role in the regulation of glucose homoeostasis via stimulation of islet and gastrointestinal GPCRs. Downstream cell signalling results in modulation of the biosynthesis, secretion, proliferation and anti-apoptotic pathways of islet and enteroendocrine cells. GPR40 and GPR120 are activated by long-chain fatty acids (>C12) with both receptors coupling to the Gαq subunit that activates the Ca(2+)-dependent pathway. GPR41 and GPR43 are stimulated by short-chain fatty acids (C2-C5), and activation results in binding to Gαi that inhibits the adenylyl cyclase pathway attenuating cAMP production. In addition, GPR43 also couples to the Gαq subunit augmenting intracellular Ca(2+) and activating phospholipase C. GPR55 is specific for cannabinoid endogenous agonists (endocannabinoids) and non-cannabinoid fatty acids, which couples to Gα12/13 and Gαq proteins, leading to enhancing intracellular Ca(2+), extracellular signal-regulated kinase 1/2 (ERK) phosphorylation and Rho kinase. GPR119 is activated by fatty acid ethanolamides and binds to Gαs utilising the adenylate cyclase pathway, which is dependent upon protein kinase A. Current research indicates that GPCR therapies may be approved for clinical use in the near future. This review focuses on the recent advances in preclinical diabetes research in the signalling and regulation of GPCRs on islet and enteroendocrine cells involved in glucose homoeostasis. PMID:26739335

  1. Improving the Mass-Limited Performance of Routine NMR Probes using Coupled Coils

    NASA Astrophysics Data System (ADS)

    Marsden, Brian; Lim, Victor; Taber, Bob; Zens, Albert

    2016-07-01

    We report a method to convert, on demand, a general use dual-broadband probe to a high performance mass-limited probe for both high band and low band nuclei. This technology uses magnetic coupling of inductors to achieve this capability. The method offers a cost effective way of increasing the performance of routine NMR probes without having to change probes or increase the overall foot print of the spectrometer.

  2. Critical role of inhomogeneities in pacing termination of cardiac reentry

    NASA Astrophysics Data System (ADS)

    Sinha, Sitabhra; Stein, Kenneth M.; Christini, David J.

    2002-09-01

    Reentry around nonconducting ventricular scar tissue, a cause of lethal arrhythmias, is typically treated by rapid electrical stimulation from an implantable cardioverter defibrillator. However, the dynamical mechanisms of termination (success and failure) are poorly understood. To elucidate such mechanisms, we study the dynamics of pacing in one- and two-dimensional models of anatomical reentry. In a crucial realistic difference from previous studies of such systems, we have placed the pacing site away from the reentry circuit. Our model-independent results suggest that with such off-circuit pacing, the existence of inhomogeneity in the reentry circuit is essential for successful termination of tachycardia under certain conditions. Considering the critical role of such inhomogeneities may lead to more effective pacing algorithms.

  3. Positive emotion reduces dyspnea during slow paced breathing.

    PubMed

    Allen, Ben; Friedman, Bruce H

    2012-05-01

    Slow breathing is used to induce cardiovascular resonance, a state associated with health benefits, but it can also increase tidal volume and associated dyspnea (respiratory discomfort). Dyspnea may be decreased by induced positive affect. In this study, 71 subjects (36 men, M = 20 years) breathed at 6 breaths per min. In condition one, subjects paced their breathing by inhaling and exhaling as a vertical bar moved up and down. In condition two, breathing was paced by a timed slideshow of positive images; subjects inhaled during a black screen and exhaled as the image appeared. Cardiac, respiratory, and self-reported dyspnea and emotional indices were recorded. Tidal volume and the intensity and unpleasantness of dyspnea were reduced when paced breathing was combined with pleasant images. These results show that positive affect can reduce dyspnea during slow paced breathing, and may have applications for induced cardiovascular resonance. PMID:22292794

  4. The PACES Summer Science Trek: A Pre-College Science

    NASA Technical Reports Server (NTRS)

    Smith, Michelle B.

    1997-01-01

    The University of Texas at El Paso (UTEP) received five-year funding to form the Pan American Center for Earth and Environmental Studies (PACES) in July 1995. PACES has as its goals to conduct research contributing to NASA's Mission to Planet Earth and to develop skilled scientists and engineers. PACES seeks to gain a more comprehensive understanding of geological, ecological and environmental processes and changes taking place in the southwestern United States and northern Mexico region. The PACES center has collaborative ties with two NASA field center (Goddard Space Flight Center and Ames Research Center) and the Jet Propulsion Laboratory. The original proposal contained no provision for outreach programs. However, at a meeting in the fall of 1995, Dan Goldin, NASA Administrator, issued the challenge that in order to accomplish NASA's goals to educate more of the citizenry in science and engineering, the Centers should take a broader perspective aimed at younger children.

  5. Photons and baryons before atoms: Improving the tight-coupling approximation

    NASA Astrophysics Data System (ADS)

    Cyr-Racine, Francis-Yan; Sigurdson, Kris

    2011-05-01

    Prior to recombination photons, electrons, and atomic nuclei rapidly scattered and behaved, almost, like a single tightly-coupled photon-baryon plasma. We investigate here the accuracy of the tight-coupling approximation commonly used to numerically evolve the baryon and photon perturbation equations at early times. By solving the exact perturbations equations with a stiff solver starting deep in the radiation-dominated epoch, we find the level of inaccuracy introduced by resorting to the standard first-order tight-coupling approximation. We develop a new second-order approximation in the inverse Thomson opacity expansion and show that it closely tracks the full solution, at essentially no extra numerical cost. We find the bias on estimates of cosmological parameters introduced by the first-order approximation is, for most parameters, negligible. Finally, we show that our second-order approximation can be used to reduce the time needed to compute cosmic microwave background angular spectra by as much as ˜17%.

  6. Studies on the coupling transformer to improve the performance of microwave ion source.

    PubMed

    Misra, Anuraag; Pandit, V S

    2014-06-01

    A 2.45 GHz microwave ion source has been developed and installed at the Variable Energy Cyclotron Centre to produce high intensity proton beam. It is operational and has already produced more than 12 mA of proton beam with just 350 W of microwave power. In order to optimize the coupling of microwave power to the plasma, a maximally flat matching transformer has been used. In this paper, we first describe an analytical method to design the matching transformer and then present the results of rigorous simulation performed using ANSYS HFSS code to understand the effect of different parameters on the transformed impedance and reflection and transmission coefficients. Based on the simulation results, we have chosen two different coupling transformers which are double ridged waveguides with ridge widths of 24 mm and 48 mm. We have fabricated these transformers and performed experiments to study the influence of these transformers on the coupling of microwave to plasma and extracted beam current from the ion source. PMID:24985808

  7. Studies on the coupling transformer to improve the performance of microwave ion source

    SciTech Connect

    Misra, Anuraag E-mail: vspandit12@gmail.com Pandit, V. S. E-mail: vspandit12@gmail.com

    2014-06-15

    A 2.45 GHz microwave ion source has been developed and installed at the Variable Energy Cyclotron Centre to produce high intensity proton beam. It is operational and has already produced more than 12 mA of proton beam with just 350 W of microwave power. In order to optimize the coupling of microwave power to the plasma, a maximally flat matching transformer has been used. In this paper, we first describe an analytical method to design the matching transformer and then present the results of rigorous simulation performed using ANSYS HFSS code to understand the effect of different parameters on the transformed impedance and reflection and transmission coefficients. Based on the simulation results, we have chosen two different coupling transformers which are double ridged waveguides with ridge widths of 24 mm and 48 mm. We have fabricated these transformers and performed experiments to study the influence of these transformers on the coupling of microwave to plasma and extracted beam current from the ion source.

  8. Improved simulation of tropospheric ozone by a global-multi-regional two-way coupling model system

    NASA Astrophysics Data System (ADS)

    Yan, Y.-Y.; Lin, J.-T.; Chen, J.; Hu, L.

    2015-09-01

    Small-scale nonlinear chemical and physical processes over pollution source regions affect the global ozone (O3) chemistry, but these processes are not captured by current global chemical transport models (CTMs) and chemistry-climate models that are limited by coarse horizontal resolutions (100-500 km, typically 200 km). These models tend to contain large (and mostly positive) tropospheric O3 biases in the Northern Hemisphere. Here we use a recently built two-way coupling system of the GEOS-Chem CTM to simulate the global tropospheric O3 in 2009. The system couples the global model (at 2.5° long. × 2° lat.) and its three nested models (at 0.667° long. × 0.5° lat.) covering Asia, North America and Europe, respectively. Benefiting from the high resolution, the nested models better capture small-scale processes than the global model alone. In the coupling system, the nested models provide results to modify the global model simulation within respective nested domains while taking the lateral boundary conditions from the global model. Due to the "coupling" effects, the two-way system significantly improves the tropospheric O3 simulation upon the global model alone, as found by comparisons with a suite of ground (1420 sites from WDCGG, GMD, EMEP, and AQS), aircraft (HIPPO and MOZAIC), and satellite measurements (two OMI products). Compared to the global model alone, the two-way coupled simulation enhances the correlation in day-to-day variation of afternoon mean O3 with the ground measurements from 0.53 to 0.68, and it reduces the mean model bias from 10.8 to 6.7 ppb in annual average afternoon O3. Regionally, the coupled model reduces the bias by 4.6 ppb over Europe, 3.9 ppb over North America, and 3.1 ppb over other regions. The two-way coupling brings O3 vertical profiles much closer to the HIPPO (for remote areas) and MOZAIC (for polluted regions) data, reducing the tropospheric (0-9 km) mean bias by 3-10 ppb at most MOZAIC sites and by 5.3 ppb for HIPPO

  9. Pacing: A concept analysis of a chronic pain intervention

    PubMed Central

    Jamieson-Lega, Kathryn; Berry, Robyn; Brown, Cary A

    2013-01-01

    BACKGROUND: The intervention of pacing is regularly recommended for chronic pain patients. However, pacing is poorly defined and appears to be interpreted in varying, potentially contradictory manners within the field of chronic pain. This conceptual lack of clarity has implications for effective service delivery and for researchers’ ability to conduct rigorous study. An examination of the background literature demonstrates that while pacing is often one part of a multidisciplinary pain management program, outcome research is hindered by a lack of a clear and shared definition of this currently ill-defined construct. OBJECTIVES: To conduct a formal concept analysis of the term ‘pacing’. METHODS: A standardized concept analysis process (including literature scoping to identify all uses of the concept, analysis to determine defining attributes of the concept and identification of model, borderline and contrary cases) was used to determine what the concept of pacing does and does not represent within the current evidence base. RESULTS: A conceptual model including the core attributes of action, time, balance, learning and self-management emerged. From these attributes, an evidence-based definition for pacing was composed and distributed to stakeholders for review. After consideration of stakeholder feedback, the emergent definition of pacing was finalized as follows: “Pacing is an active self-management strategy whereby individuals learn to balance time spent on activity and rest for the purpose of achieving increased function and participation in meaningful activities”. CONCLUSION: The findings of the present concept analysis will help to standardize the use and definition of the term pacing across disciplines for the purposes of both pain management and research. PMID:23717825

  10. The Efficacy of Self-Paced Study in Multitrial Learning

    ERIC Educational Resources Information Center

    de Jonge, Mario; Tabbers, Huib K.; Pecher, Diane; Jang, Yoonhee; Zeelenberg, René

    2015-01-01

    In 2 experiments we investigated the efficacy of self-paced study in multitrial learning. In Experiment 1, native speakers of English studied lists of Dutch-English word pairs under 1 of 4 imposed fixed presentation rate conditions (24 × 1 s, 12 × 2 s, 6 × 4 s, or 3 × 8 s) and a self-paced study condition. Total study time per list was equated for…

  11. An improvement in mass flux convective parameterizations and its impact on seasonal simulations using a coupled model

    NASA Astrophysics Data System (ADS)

    Elsayed Yousef, Ahmed; Ehsan, M. Azhar; Almazroui, Mansour; Assiri, Mazen E.; Al-Khalaf, Abdulrahman K.

    2015-11-01

    A new closure and a modified detrainment for the simplified Arakawa-Schubert (SAS) cumulus parameterization scheme are proposed. In the modified convective scheme which is named as King Abdulaziz University (KAU) scheme, the closure depends on both the buoyancy force and the environment mean relative humidity. A lateral entrainment rate varying with environment relative humidity is proposed and tends to suppress convection in a dry atmosphere. The detrainment rate also varies with environment relative humidity. The KAU scheme has been tested in a single column model (SCM) and implemented in a coupled global climate model (CGCM). Increased coupling between environment and clouds in the KAU scheme results in improved sensitivity of the depth and strength of convection to environmental humidity compared to the original SAS scheme. The new scheme improves precipitation simulation with better representations of moisture and temperature especially during suppressed convection periods. The KAU scheme implemented in the Seoul National University (SNU) CGCM shows improved precipitation over the tropics. The simulated precipitation pattern over the Arabian Peninsula and Northeast African region is also improved.

  12. Testing cloud microphysics parameterizations in NCAR CAM5 with ISDAC and M-PACE observations

    SciTech Connect

    Liu X.; Lin W.; Xie, S.; Boyle, J.; Klein, S. A.; Shi, X.; Wang, Z.; Ghan, S. J.; Earle, M.; Liu, P. S. K.; Zelenyuk, A.

    2011-12-24

    Arctic clouds simulated by the National Center for Atmospheric Research (NCAR) Community Atmospheric Model version 5 (CAM5) are evaluated with observations from the U.S. Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) Indirect and Semi-Direct Aerosol Campaign (ISDAC) and Mixed-Phase Arctic Cloud Experiment (M-PACE), which were conducted at its North Slope of Alaska site in April 2008 and October 2004, respectively. Model forecasts for the Arctic spring and fall seasons performed under the Cloud-Associated Parameterizations Testbed framework generally reproduce the spatial distributions of cloud fraction for single-layer boundary-layer mixed-phase stratocumulus and multilayer or deep frontal clouds. However, for low-level stratocumulus, the model significantly underestimates the observed cloud liquid water content in both seasons. As a result, CAM5 significantly underestimates the surface downward longwave radiative fluxes by 20-40 W m{sup -2}. Introducing a new ice nucleation parameterization slightly improves the model performance for low-level mixed-phase clouds by increasing cloud liquid water content through the reduction of the conversion rate from cloud liquid to ice by the Wegener-Bergeron-Findeisen process. The CAM5 single-column model testing shows that changing the instantaneous freezing temperature of rain to form snow from -5 C to -40 C causes a large increase in modeled cloud liquid water content through the slowing down of cloud liquid and rain-related processes (e.g., autoconversion of cloud liquid to rain). The underestimation of aerosol concentrations in CAM5 in the Arctic also plays an important role in the low bias of cloud liquid water in the single-layer mixed-phase clouds. In addition, numerical issues related to the coupling of model physics and time stepping in CAM5 are responsible for the model biases and will be explored in future studies.

  13. The impact of the perception of rhythmic music on self-paced oscillatory movements.

    PubMed

    Peckel, Mathieu; Pozzo, Thierry; Bigand, Emmanuel

    2014-01-01

    Inspired by theories of perception-action coupling and embodied music cognition, we investigated how rhythmic music perception impacts self-paced oscillatory movements. In a pilot study, we examined the kinematic parameters of self-paced oscillatory movements, walking and finger tapping using optical motion capture. In accordance with biomechanical constraints accounts of motion, we found that movements followed a hierarchical organization depending on the proximal/distal characteristic of the limb used. Based on these findings, we were interested in knowing how and when the perception of rhythmic music could resonate with the motor system in the context of these constrained oscillatory movements. In order to test this, we conducted an experiment where participants performed four different effector-specific movements (lower leg, whole arm and forearm oscillation and finger tapping) while rhythmic music was playing in the background. Musical stimuli consisted of computer-generated MIDI musical pieces with a 4/4 metrical structure. The musical tempo of each song increased from 60 BPM to 120 BPM by 6 BPM increments. A specific tempo was maintained for 20 s before a 2 s transition to the higher tempo. The task of the participant was to maintain a comfortable pace for the four movements (self-paced) while not paying attention to the music. No instruction on whether to synchronize with the music was given. Results showed that participants were distinctively influenced by the background music depending on the movement used with the tapping task being consistently the most influenced. Furthermore, eight strategies put in place by participants to cope with the task were unveiled. Despite not instructed to do so, participants also occasionally synchronized with music. Results are discussed in terms of the link between perception and action (i.e., motor/perceptual resonance). In general, our results give support to the notion that rhythmic music is processed in a motoric

  14. The impact of the perception of rhythmic music on self-paced oscillatory movements

    PubMed Central

    Peckel, Mathieu; Pozzo, Thierry; Bigand, Emmanuel

    2014-01-01

    Inspired by theories of perception-action coupling and embodied music cognition, we investigated how rhythmic music perception impacts self-paced oscillatory movements. In a pilot study, we examined the kinematic parameters of self-paced oscillatory movements, walking and finger tapping using optical motion capture. In accordance with biomechanical constraints accounts of motion, we found that movements followed a hierarchical organization depending on the proximal/distal characteristic of the limb used. Based on these findings, we were interested in knowing how and when the perception of rhythmic music could resonate with the motor system in the context of these constrained oscillatory movements. In order to test this, we conducted an experiment where participants performed four different effector-specific movements (lower leg, whole arm and forearm oscillation and finger tapping) while rhythmic music was playing in the background. Musical stimuli consisted of computer-generated MIDI musical pieces with a 4/4 metrical structure. The musical tempo of each song increased from 60 BPM to 120 BPM by 6 BPM increments. A specific tempo was maintained for 20 s before a 2 s transition to the higher tempo. The task of the participant was to maintain a comfortable pace for the four movements (self-paced) while not paying attention to the music. No instruction on whether to synchronize with the music was given. Results showed that participants were distinctively influenced by the background music depending on the movement used with the tapping task being consistently the most influenced. Furthermore, eight strategies put in place by participants to cope with the task were unveiled. Despite not instructed to do so, participants also occasionally synchronized with music. Results are discussed in terms of the link between perception and action (i.e., motor/perceptual resonance). In general, our results give support to the notion that rhythmic music is processed in a motoric

  15. Feasibility of Leadless Cardiac Pacing Using Injectable Magnetic Microparticles.

    PubMed

    Rotenberg, Menahem Y; Gabay, Hovav; Etzion, Yoram; Cohen, Smadar

    2016-01-01

    A noninvasive, effective approach for immediate and painless heart pacing would have invaluable implications in several clinical scenarios. Here we present a novel strategy that utilizes the well-known mechano-electric feedback of the heart to evoke cardiac pacing, while relying on magnetic microparticles as leadless mechanical stimulators. We demonstrate that after localizing intravenously-injected magnetic microparticles in the right ventricular cavity using an external electromagnet, the application of magnetic pulses generates mechanical stimulation that provokes ventricular overdrive pacing in the rat heart. This temporary pacing consistently managed to revert drug-induced bradycardia, but could only last up to several seconds in the rat model, most likely due to escape of the particles between the applied pulses using our current experimental setting. In a pig model with open chest, MEF-based pacing was induced by banging magnetic particles and has lasted for a longer time. Due to overheating of the electromagnet, we intentionally terminated the experiments after 2 min. Our results demonstrate for the first time the feasibility of external leadless temporary pacing, using injectable magnetic microparticles that are manipulated by an external electromagnet. This new approach can have important utilities in clinical settings in which immediate and painless control of cardiac rhythm is required. PMID:27091192

  16. Feasibility of Leadless Cardiac Pacing Using Injectable Magnetic Microparticles

    PubMed Central

    Rotenberg, Menahem Y.; Gabay, Hovav; Etzion, Yoram; Cohen, Smadar

    2016-01-01

    A noninvasive, effective approach for immediate and painless heart pacing would have invaluable implications in several clinical scenarios. Here we present a novel strategy that utilizes the well-known mechano-electric feedback of the heart to evoke cardiac pacing, while relying on magnetic microparticles as leadless mechanical stimulators. We demonstrate that after localizing intravenously-injected magnetic microparticles in the right ventricular cavity using an external electromagnet, the application of magnetic pulses generates mechanical stimulation that provokes ventricular overdrive pacing in the rat heart. This temporary pacing consistently managed to revert drug-induced bradycardia, but could only last up to several seconds in the rat model, most likely due to escape of the particles between the applied pulses using our current experimental setting. In a pig model with open chest, MEF-based pacing was induced by banging magnetic particles and has lasted for a longer time. Due to overheating of the electromagnet, we intentionally terminated the experiments after 2 min. Our results demonstrate for the first time the feasibility of external leadless temporary pacing, using injectable magnetic microparticles that are manipulated by an external electromagnet. This new approach can have important utilities in clinical settings in which immediate and painless control of cardiac rhythm is required. PMID:27091192

  17. Optimum pacing mode for patients with angina pectoris.

    PubMed Central

    Kenny, R A; Ingram, A; Mitsuoka, T; Walsh, K; Sutton, R

    1986-01-01

    A within patient double blind prospective study of symptoms and exercise tolerance was designed to determine the preferred pacing mode in 10 patients with programmable dual chamber pacemakers who also had angina pectoris. Patients were randomly allocated to one month in each of the following modes: ventricular pacing at 70 beats/min (VVI) or atrioventricular synchronous upper rate 150 beats/min (DDD 150) or 100 beats/min (DDD 100). Medications were unchanged throughout the study; none was taking beta blockers. At the end of each month patients underwent an exercise test. During each month patients recorded symptoms and their preferred pacing mode. DDD 100 was the preferred mode (seven patients). There was significantly less chest pain with this mode than with either of the other modes. There were significantly more episodes of dizziness in VVI, and two patients who developed pacemaker syndrome were unable to complete the pacing period. Three patients developed angina during exercise testing in DDD 150. Atrial synchronous ventricular pacing is better than ventricular pacing for the control of symptoms in patients with angina pectoris provided that the upper atrial tracking rate is limited. PMID:3790382

  18. PACE and the Federal Housing Finance Agency (FHFA)

    SciTech Connect

    Zimring, Mark; Fuller, Merrian

    2010-03-17

    The FHFA regulates Fannie Mae, Freddie Mac, and the 12 Federal Home Loan Banks (the government-sponsored enterprises - GSEs). On June 18, 2009, James B. Lockhart III, then Director of FHFA, released a letter expressing concern about the negative impact of energy loan tax assessment programs (ELTAPs) - also known as Property Assessed Clean Energy (PACE) programs - on both the housing finance system and homeowner program participants. Subsequently, a number of PACE proponents responded to the concerns laid out in the FHFA letter. In early Fall 2009, word circulated that FHFA was planning to follow its June letter with guidance to other agencies, possibly including Fannie Mae and Freddie Mac, discouraging them from buying loans on properties subject to PACE-type assessment liens. This triggered a second round of stakeholder letters, several of which were addressed to President Obama. On October 18, 2009, the White House, in what some believe was an attempt to obviate the need for FHFA guidance, released a Policy Framework for PACE Financing Programs that outlined best practices guidance for homeowner and lender protection. As of February 2010, FHFA and the GSEs have agreed to monitor PACE programs and work with stakeholders and the Administration to consider additional guidance beyond the Policy Framework and to collect more information on PACE program efficacy and risks. A summary of the communications timeline and highlights of the communications are provided.

  19. Specific Intensity for Peaking: Is Race Pace the Best Option?

    PubMed Central

    Munoz, Iker; Seiler, Stephen; Alcocer, Alberto; Carr, Natasha; Esteve-Lanao, Jonathan

    2015-01-01

    Background: The peaking period for endurance competition is characterized for a relative increase of the intensity of training, after a longer period of training relatively dominated by lower intensity and higher volume Objectives: The present study was designed to compare physiological and 10 km performance effects of high intensity training (HIT) versus race pace interval training (RP) during peaking for competition in well-trained runners. Patients and Methods: 13 athletes took part in the study, they were divided into two groups: HIT and RP. HIT performed short intervals at ~105% of the maximal aerobic velocity (MAV), while RP trained longer intervals at a speed of ~90% of the MAV (a speed approximating 10 km race pace). After 12 weeks of baseline training, the athletes trained for 6 weeks under one of the two peaking regimes. Subjects performed 10 km prior to and after the intervention period. The total load of training was matched between groups during the treatment phase. Subjects completed a graded treadmill running test until volitional exhaustion prior to each 10 km race. MAV was determined as the minimal velocity eliciting maximal oxygen consumption (VO2max). Results: Both groups significantly improved their 10 km time (35 minutes 29 seconds ± 1 minutes 41 seconds vs 34 minutes 53 seconds ± 1 minutes 55 seconds, P < 0.01 for HIT; 35 minutes 27 seconds ± 1 minutes 40 seconds vs 34 minutes 53 seconds ± 1 minutes 18 seconds P < 0.01 for RP). VO2max increased after HIT (69 ± 3.6 vs 71.5 ± 4.2 ml.Kg-1.min-1, P < 0.05); while it didn’t for RP (68.4 ± 6 vs 69.8 ± 3 ml.Kg-1.min-1, p>0.05). In contrast, running economy decreased significantly after HIT (210 ± 6 ml.Kg-1.km-1 vs 218 ± 9, P < 0.05). Conclusions: A 6 week period of training at either 105% of MAV or 90% of MAV yielded similar performance gains in a 10km race performed at ~90% MAV. Therefore, the physiological impact of HIT training seems to be positive for VO2max but negative for running

  20. The Pace of Perceivable Extreme Climate Change

    NASA Astrophysics Data System (ADS)

    Tan, X.; Gan, T. Y.

    2015-12-01

    When will the signal of obvious changes in extreme climate emerge over climate variability (Time of Emergence, ToE) is a key question for planning and implementing measures to mitigate the potential impact of climate change to natural and human systems that are generally adapted to potential changes from current variability. We estimated ToEs for the magnitude, duration and frequency of global extreme climate represented by 24 extreme climate indices (16 for temperature and 8 for precipitation) with different thresholds of the signal-to-noise (S/N) ratio based on projections of CMIP5 global climate models under RCP8.5 and RCP4.5 for the 21st century. The uncertainty of ToE is assessed by using 3 different methods to calculate S/N for each extreme index. Results show that ToEs of the projected extreme climate indices based on the RCP4.5 climate scenarios are generally projected to happen about 20 years later than that for the RCP8.5 climate scenarios. Under RCP8.5, the projected magnitude, duration and frequency of extreme temperature on Earth will all exceed 2 standard deviations by 2100, and the empirical 50th percentile of the global ToE for the frequency and magnitude of hot (cold) extreme are about 2040 and 2054 (2064 and 2054) for S/N > 2, respectively. The 50th percentile of global ToE for the intensity of extreme precipitation is about 2030 and 2058 for S/N >0.5 and S/N >1, respectively. We further evaluated the exposure of ecosystems and human societies to the pace of extreme climate change by determining the year of ToE for various extreme climate indices projected to occur over terrestrial biomes, marine realms and major urban areas with large populations. This was done by overlaying terrestrial, ecoregions and population maps with maps of ToE derived, to extract ToEs for these regions. Possible relationships between GDP per person and ToE are also investigated by relating the mean ToE for each country and its average value of GDP per person.

  1. Spontaneous Velocity Effect of Musical Expression on Self-Paced Walking.

    PubMed

    Buhmann, Jeska; Desmet, Frank; Moens, Bart; Van Dyck, Edith; Leman, Marc

    2016-01-01

    The expressive features of music can influence the velocity of walking. So far, studies used instructed (and intended) synchronization. But is this velocity effect still present with non-instructed (spontaneous) synchronization? To figure that out, participants were instructed to walk in their own comfort tempo on an indoor track, first in silence and then with tempo-matched music. We compared velocities of silence and music conditions. The results show that some music has an activating influence, increasing velocity and motivation, while other music has a relaxing influence, decreasing velocity and motivation. The influence of musical expression on the velocity of self-paced walking can be predicted with a regression model using only three sonic features explaining 56% of the variance. Phase-coherence between footfall and beat did not contribute to the velocity effect, due to its implied fixed pacing. The findings suggest that the velocity effect depends on vigor entrainment that influences both stride length and pacing. Our findings are relevant for preventing injuries, for gait improvement in walking rehabilitation, and for improving performance in sports activities. PMID:27167064

  2. Spontaneous Velocity Effect of Musical Expression on Self-Paced Walking

    PubMed Central

    Buhmann, Jeska; Desmet, Frank; Moens, Bart; Van Dyck, Edith; Leman, Marc

    2016-01-01

    The expressive features of music can influence the velocity of walking. So far, studies used instructed (and intended) synchronization. But is this velocity effect still present with non-instructed (spontaneous) synchronization? To figure that out, participants were instructed to walk in their own comfort tempo on an indoor track, first in silence and then with tempo-matched music. We compared velocities of silence and music conditions. The results show that some music has an activating influence, increasing velocity and motivation, while other music has a relaxing influence, decreasing velocity and motivation. The influence of musical expression on the velocity of self-paced walking can be predicted with a regression model using only three sonic features explaining 56% of the variance. Phase-coherence between footfall and beat did not contribute to the velocity effect, due to its implied fixed pacing. The findings suggest that the velocity effect depends on vigor entrainment that influences both stride length and pacing. Our findings are relevant for preventing injuries, for gait improvement in walking rehabilitation, and for improving performance in sports activities. PMID:27167064

  3. Biomechanically and electromyographically assessed load on the spine in self-paced and force-paced lifting work.

    PubMed

    Leskinen, T P; Stålhammar, H R; Rautanen, M T; Troup, J D

    1992-01-01

    The purpose of this study was to measure dose of spinal load when different pacing methods were applied to lifting work and to develop methodology for such measurements. The compressive load on the spine computed by a dynamic biomechanical model and the electromyographic activity of back muscles were used for describing the spinal load. Five men and five women worked in a laboratory on two days lifting a box up and down for 30 min on both days, on one day force-paced (4 lifts/min), and on the other self-paced in random order. The weight of the box was rated by the subjects to be acceptable for the work done. The lift rate of our female subjects was higher and that of the male subjects lower in self-paced than in force-paced work. There were no significant differences in peak lumbosacral compressions nor in the amplitude distributions of electromyography between the two pacing methods. The biomechanically-calculated compressive forces on the spine were lower (about 2.7 kN for the men and 2.3 kN for women) than the biomechanical recommendations for safe lifting, but the EMG activity showed quite high peaks so that for 1% of work time the activity was on women above 60% and on men above 40% of the activity during maximum isometric voluntary test contraction. PMID:1633794

  4. A Low-Cost Simulation Model for R-Wave Synchronized Atrial Pacing in Pediatric Patients with Postoperative Junctional Ectopic Tachycardia

    PubMed Central

    Michel, Miriam; Egender, Friedemann; Heßling, Vera; Dähnert, Ingo; Gebauer, Roman

    2016-01-01

    Background Postoperative junctional ectopic tachycardia (JET) occurs frequently after pediatric cardiac surgery. R-wave synchronized atrial (AVT) pacing is used to re-establish atrioventricular synchrony. AVT pacing is complex, with technical pitfalls. We sought to establish and to test a low-cost simulation model suitable for training and analysis in AVT pacing. Methods A simulation model was developed based on a JET simulator, a simulation doll, a cardiac monitor, and a pacemaker. A computer program simulated electrocardiograms. Ten experienced pediatric cardiologists tested the model. Their performance was analyzed using a testing protocol with 10 working steps. Results Four testers found the simulation model realistic; 6 found it very realistic. Nine claimed that the trial had improved their skills. All testers considered the model useful in teaching AVT pacing. The simulation test identified 5 working steps in which major mistakes in performance test may impede safe and effective AVT pacing and thus permitted specific training. The components of the model (exclusive monitor and pacemaker) cost less than $50. Assembly and training-session expenses were trivial. Conclusions A realistic, low-cost simulation model of AVT pacing is described. The model is suitable for teaching and analyzing AVT pacing technique. PMID:26943363

  5. Rapid Recovery in Sub-Optimal Readers in Wales through a Self-Paced Computer-Based Reading Programme

    ERIC Educational Resources Information Center

    Reed, Phil; Hughes, Antony; Phillips, Gordon

    2013-01-01

    Basic literacy skills underlie much future adult functioning, and are targeted in children through a variety of means. Children with identified special needs in reading were exposed to a self-paced computer-based reading programme that focused on improving phonetic ability. Exposure was limited to three, 40-minute sessions a week, for 10 weeks.…

  6. Improvements for operational baseband tune and coupling measurements and feedback at RHIC

    SciTech Connect

    Wilinski, M.; Dawson, C.; Degen, C.; Marusic, A.; Mernick, K.; Minty, M.; Russo, T.

    2010-05-02

    Throughout RHIC Run-9 (polarized protons) and Run-10 (gold), numerous modifications to the Baseband Tune (BBQ) system were made. Hardware and software improvements resulted in improved resolution and control, allowing the system to overcome challenges from competing 60Hz mains harmonics, other spectral content, and other beam issues. Test points from the Analog Front End (AFE) were added and connected to diagnostics that allow us to view signals, such as frequency spectra on a Sr785 dynamic signal analyser (DSA), in real time. Also, additional data can now be logged using a National Instruments DAQ (NI-DAQ). Development time using tune feedback to obtain full-energy beams at RHIC has been significantly reduced from many ramps over a few weeks, to just a few ramps over several hours. For many years BBQ was an expert-only system, but the many improvements allowed BBQ to finally be handed over to the Operations Staff for routine control.

  7. Improvements for determining the modulation transfer function of charge-coupled devices by the speckle method.

    PubMed

    Pozo, A M; Ferrero, A; Rubiño, M; Campos, J; Pons, A

    2006-06-26

    We present and evaluate two corrections applicable in determining the modulation transfer function (MTF) of a charge-coupled device (CCD) by the speckle method that minimize its uncertainty: one for the low frequency region and another for the high frequency region. The correction at the low-spatial-frequency region enables attenuation of the high power-spectral-density values that arise from the field and CCD response non-uniformities. In the high-spatial-frequency region the results show that the distance between the CCD and the aperture is critical and significantly influences the MTF; a variation of 1 mm in the distance can cause a root-mean-square error in the MTF higher than 10%. We propose a simple correction that minimizes the experimental error committed in positioning the CCD and that diminishes the error to 0.43%. PMID:19516762

  8. Improvements for determining the modulation transfer function of charge-coupled devices by the speckle method

    NASA Astrophysics Data System (ADS)

    Pozo, A. M.; Ferrero, A.; Rubiño, M.; Campos, J.; Pons, A.

    2006-06-01

    We present and evaluate two corrections applicable in determining the modulation transfer function (MTF) of a charge-coupled device (CCD) by the speckle method that minimize its uncertainty: one for the low frequency region and another for the high frequency region. The correction at the low-spatial-frequency region enables attenuation of the high power-spectral-density values that arise from the field and CCD response non-uniformities. In the high-spatial-frequency region the results show that the distance between the CCD and the aperture is critical and significantly influences the MTF; a variation of 1 mm in the distance can cause a root-mean-square error in the MTF higher than 10%. We propose a simple correction that minimizes the experimental error committed in positioning the CCD and that diminishes the error to 0.43%.

  9. 42 CFR 460.90 - PACE benefits under Medicare and Medicaid.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 4 2012-10-01 2012-10-01 false PACE benefits under Medicare and Medicaid. 460.90 Section 460.90 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN... FOR THE ELDERLY (PACE) PACE Services § 460.90 PACE benefits under Medicare and Medicaid. If a...

  10. Coupling the Biophysical and Social Dimensions of Wildfire Risk to Improve Wildfire Mitigation Planning.

    PubMed

    Ager, Alan A; Kline, Jeffrey D; Fischer, A Paige

    2015-08-01

    We describe recent advances in biophysical and social aspects of risk and their potential combined contribution to improve mitigation planning on fire-prone landscapes. The methods and tools provide an improved method for defining the spatial extent of wildfire risk to communities compared to current planning processes. They also propose an expanded role for social science to improve understanding of community-wide risk perceptions and to predict property owners' capacities and willingness to mitigate risk by treating hazardous fuels and reducing the susceptibility of dwellings. In particular, we identify spatial scale mismatches in wildfire mitigation planning and their potential adverse impact on risk mitigation goals. Studies in other fire-prone regions suggest that these scale mismatches are widespread and contribute to continued wildfire dwelling losses. We discuss how risk perceptions and behavior contribute to scale mismatches and how they can be minimized through integrated analyses of landscape wildfire transmission and social factors that describe the potential for collaboration among landowners and land management agencies. These concepts are then used to outline an integrated socioecological planning framework to identify optimal strategies for local community risk mitigation and improve landscape-scale prioritization of fuel management investments by government entities. PMID:25968881

  11. Testing a four-dimensional variational data assimilation method using an improved intermediate coupled model for ENSO analysis and prediction

    NASA Astrophysics Data System (ADS)

    Gao, Chuan; Wu, Xinrong; Zhang, Rong-Hua

    2016-07-01

    A four-dimensional variational (4D-Var) data assimilation method is implemented in an improved intermediate coupled model (ICM) of the tropical Pacific. A twin experiment is designed to evaluate the impact of the 4D-Var data assimilation algorithm on ENSO analysis and prediction based on the ICM. The model error is assumed to arise only from the parameter uncertainty. The "observation" of the SST anomaly, which is sampled from a "truth" model simulation that takes default parameter values and has Gaussian noise added, is directly assimilated into the assimilation model with its parameters set erroneously. Results show that 4D-Var effectively reduces the error of ENSO analysis and therefore improves the prediction skill of ENSO events compared with the non-assimilation case. These results provide a promising way for the ICM to achieve better real-time ENSO prediction.

  12. [Analysis of fusion waves created with temporal pacing].

    PubMed

    Ueda, M; Shigemi, K; Hayashi, K; Kakihara, K; Nakajima, Y; Fukushima, H; Tanaka, Y

    1998-08-01

    Fifty-five beats of fusion waves were recorded continuously with an audio digital tape and the tape was re-played for analysis. A 45-year-old male (56 kg, 175 cm) with cervical spondylosis was scheduled to undergo laminoplasty of the cervical vertebral (C2-C6). A temporal ventricular (VVI mode) pacing lead was inserted from the right cubital vein to the right ventricular apex for preventing bradycardia while manipulating the medulla. The height of the R wave decreased gradually and the depth of S wave increased in the earlier period of fusion beats and it was reversed later. The narrow QRS width indicated that the electrode was placed near the cardiac conducting system. The gradually increasing intervals between P waves activated the pacing, and the P wave intervals recovered inhibiting the pacing. During the recovery phase, some beats were still activated by pacing instead of depressing the rate below the original rate. These beats suggest the importance of considering the atrial-ventricular conducting time. Arterial pressure fluctuated only slightly during the 'fusion beats, suggesting that despite the abnormality in the cardiac conduction system due to pacing, contraction of the ventricular muscles was only slightly affected in this case. PMID:9753972

  13. Phrenic Nerve Stimulation for Diaphragm Pacing in a Quadriplegic Patient

    PubMed Central

    Kim, Deog-ryung; Kim, Il-sup; Hong, Jae Taek

    2013-01-01

    Chronic hypoventilation due to injury to the brain stem respiratory center or high cervical cord (above the C3 level) can result in dependence to prolonged mechanical ventilation with tracheostomy, frequent nosocomial pneumonia, and prolonged hospitalization. Diaphragm pacing through electrical stimulation of the phrenic nerve is an established treatment for central hypoventilation syndrome. We performed chronic phrenic nerve stimulation for diaphragm pacing with the spinal cord stimulator for pain control in a quadriplegic patient with central apnea due to complete spinal cord injury at the level of C2 from cervical epidural hematoma. After diaphragmatic pacing, the patient who was completely dependent on the mechanical ventilator could ambulate up to three hours every day without aid of mechanical ventilation during the 12 months of follow-up. Diaphragm pacing through unilateral phrenic nerve stimulation with spinal cord stimulator was feasible in an apneic patient with complete quadriplegia who was completely dependent on mechanical ventilation. Diaphragm pacing with the spinal cord stimulator is feasible and effective for the treatment of the central hypoventilation syndrome. PMID:24294464

  14. T wave alternans during exercise and atrial pacing in humans

    NASA Technical Reports Server (NTRS)

    Hohnloser, S. H.; Klingenheben, T.; Zabel, M.; Li, Y. G.; Albrecht, P.; Cohen, R. J.

    1997-01-01

    INTRODUCTION: Evidence is accumulating that microvolt T wave alternans (TWA) is a marker of increased risk for ventricular tachyarrhythmias. Initially, atrial pacing was used to elevate heart rate and elicit TWA. More recently, a noninvasive approach has been developed that elevates heart rate using exercise. METHODS AND RESULTS: In 30 consecutive patients with a history of ventricular tachyarrhythmias, the spectral method was used to detect TWA during both atrial pacing and submaximal exercise testing. The concordance rate for the presence or absence of TWA using the two measurement methods was 84%. There was a patient-specific heart rate threshold for the detection of TWA that averaged 100 +/- 14 beats/min during exercise compared with 97 +/- 9 beats/min during right atrial pacing (P = NS). Beyond this threshold, there was a significant and comparable increase in level of TWA with decreasing pacing cycle length and increasing exercise heart rates. CONCLUSIONS: The present study is the first to demonstrate that microvolt TWA can be assessed reliably and noninvasively during exercise stress. There is a patient-specific heart rate threshold beyond which TWA continues to increase with increasing heart rates. Heart rate thresholds for the onset of TWA measured during atrial pacing and exercise stress were comparable, indicating that heart rate alone appears to be the main factor of determining the onset of TWA during submaximal exercise stress.

  15. Aluminum nanoparticles for plasmon-improved coupling of light into silicon.

    PubMed

    Villesen, T F; Uhrenfeldt, Christian; Johansen, B; Hansen, J Lundsgaard; Ulriksen, H U; Larsen, Arne Nylandsted

    2012-03-01

    This paper investigates the improved photo-current response obtained by depositing Al nanoparticles on top of a Si diode. Well defined Al nanodiscs with a diameter and height of 100 nm are produced on the surface of a Si diode using electron-beam lithography, and the change in photo-current generation is characterized. A blue shift of the photo-current response is demonstrated, substantially improving the relation between gains and losses compared to what is typically observed in similar schemes using Ag nanoparticles. Enhanced photo-current response is observed in diodes with Al particles on the surface at all wavelengths larger than ≈465 nm, thereby minimizing the losses in the blue range usually reported with Ag nanoparticles on the surface. PMID:22293458

  16. Weak-microcavity organic light-emitting diodes with improved light out-coupling.

    PubMed

    Cho, Sang-Hwan; Song, Young-Woo; Lee, Joon-gu; Kim, Yoon-Chang; Lee, Jong Hyuk; Ha, Jaeheung; Oh, Jong-Suk; Lee, So Young; Lee, Sun Young; Hwang, Kyu Hwan; Zang, Dong-Sik; Lee, Yong-Hee

    2008-08-18

    We propose and demonstrate weak-microcavity organic light-emitting diode (OLED) displays with improved light-extraction and viewing-angle characteristics. A single pair of low- and high-index layers is inserted between indium tin oxide (ITO) and a glass substrate. The electroluminescent (EL) efficiencies of discrete red, green, and blue weak-microcavity OLEDs are enhanced by 56%, 107%, and 26%, respectively, with improved color purity. Moreover, full-color passive-matrix bottom-emitting OLED displays are fabricated by employing low-index layers of two thicknesses. As a display, the EL efficiency of white color was 27% higher than that of a conventional OLED display. PMID:18711500

  17. Improved photoelectric conversion efficiency from titanium oxide-coupled tin oxide nanoparticles formed in flame

    NASA Astrophysics Data System (ADS)

    Gu, Feng; Huang, Wenjuan; Wang, Shufen; Cheng, Xing; Hu, Yanjie; Li, Chunzhong

    2014-12-01

    The charge losses as a result of recombination to redox electrolyte and dye cation make tin oxide (SnO2)-based dye-sensitized solar cells (DSSCs) particularly inferior when compared with its titanium oxide (TiO2) counterpart. In this article, TiO2 nanocrystal is sealed in SnO2 by a modified flame spray pyrolysis (FSP) approach and the recombination losses to dye cation of SnO2 photoanode are effectively suppressed due to the negatively shifted Fermi level with the formation of bandedge-engineered core/shell structure. The fabricated TiO2@SnO2 (TSN)-device shows an open circuit voltage of 0.59 V and an efficiency of 3.82%, significantly better than those of the TiO2-, and SnO2-DSSCs devices. After surface modification, the conversion efficiency could be further improved to 7.87% while the open circuit voltage reaches 0.70 V. The higher efficiency of the TSN-based device is attributed to the enhanced electron injection arising from decreased interfacial charge recombination losses and improved electron transport. This strategy renders a new concept for further improvement of photovoltaic performance by engineering the dynamics of electron transport and recombination in DSSCs.

  18. Thermal reliability and performance improvement of close-coupled catalytic converter

    SciTech Connect

    Hijikata, Toshihiko; Kurachi, Hiroshi; Katsube, Fumio; Honacker, H. van

    1996-09-01

    This paper proposes a high temperature catalytic converter design using a ceramic substrate and intumescent matting. It also describes the improvement of converter performance using an advanced thin wall ceramic substrate. Due to future tightening of emission regulations and improvement of fuel economy, higher exhaust gas temperatures are suggested. Therefore, reduction of thermal reliability of an intumescent mat will be a concern because the catalytic converter will be exposed to high temperatures. For this reason, a new design converter has been developed using a dual cone structure for both the inlet and outlet cones. This minimizes heat conduction through the cone and decreases the temperature affecting the mat area. This design converter, without the use of a heat-shield, reduces the converter surface temperature to 441 C despite a catalyst bed temperature of 1,050 C. The long term durability of the converter is demonstrated by the hot vibration test. Since the new design converter does not need a heat-shield, the catalyst diameter can be enlarged by the width of the air gap used in the current design converter. By using an advanced thin wall ceramic substrate, such as 0.11 mm/620 kcpsm (4 mil/400 cpsi), it is possible to improve emission performance and pressure drop compared with the conventional 0.16 mm/620 kcpsm (6 mil/400 cpsi) ceramic substrate.

  19. Improvement and Analysis of Computational Methods for Prediction of Residual Dipolar Couplings

    PubMed Central

    Berlin, Konstantin; O’Leary, Dianne P.; Fushman, David

    2009-01-01

    We describe a new, computationally effcient method for computing the molecular alignment tensor based on the molecular shape. The increase in speed is achieved by re-expressing the problem as one of numerical integration, rather than a simple uniform sampling (as in the PALES method), and by using a convex hull rather than a detailed representation of the surface of a molecule. This method is applicable to bicelles, PEG/hexanol, and other alignment media that can be modeled by steric restrictions introduced by a planar barrier. This method is used to further explore and compare various representations of protein shape by an equivalent ellipsoid. We also examine the accuracy of the alignment tensor and residual dipolar couplings (RDC) prediction using various ab initio methods. We separately quantify the inaccuracy in RDC prediction caused by the inaccuracy in the orientation and in the magnitude of the alignment tensor, concluding that orientation accuracy is much more important in accurate prediction of RDCs. PMID:19700353

  20. Improved dynamics and gravitational collapse of tachyon field coupled with a barotropic fluid

    NASA Astrophysics Data System (ADS)

    Marto, João; Tavakoli, Yaser; Moniz, Paulo Vargas

    2015-01-01

    We consider a spherically symmetric gravitational collapse of a tachyon field with an inverse square potential, which is coupled with a barotropic fluid. By employing an holonomy correction imported from loop quantum cosmology (LQC), we analyze the dynamics of the collapse within a semiclassical description. Using a dynamical system approach, we find that the stable fixed points given by the standard general relativistic setting turn into saddle points in the present context. This provides a new dynamics in contrast to the black hole and naked singularities solutions appearing in the classical model. Our results suggest that classical singularities can be avoided by quantum gravity effects and are replaced by a bounce. By a thorough numerical studies we show that, depending on the barotropic parameter γ, there exists a class of solutions corresponding to either a fluid or a tachyon dominated regimes. Furthermore, for the case γ 1, we find an interesting tracking behavior between the tachyon and the fluid leading to a dust-like collapse. In addition, we show that, there exists a threshold scale which determines when an outward energy flux emerges, as a nonsingular black hole is forming, at the corresponding collapse final stages.

  1. Improved Dyson series expansion for steady-state quantum transport beyond the weak coupling limit: divergences and resolution.

    PubMed

    Thingna, Juzar; Zhou, Hangbo; Wang, Jian-Sheng

    2014-11-21

    We present a general theory to calculate the steady-state heat and electronic currents for nonlinear systems using a perturbative expansion in the system-bath coupling. We explicitly demonstrate that using the truncated Dyson-series leads to divergences in the steady-state limit, thus making it impossible to be used for actual applications. In order to resolve the divergences, we propose a unique choice of initial condition for the reduced density matrix, which removes the divergences at each order. Our approach not only allows us to use the truncated Dyson-series, with a reasonable choice of initial condition, but also gives the expected result that the steady-state solutions should be independent of initial preparations. Using our improved Dyson series we evaluate the heat and electronic currents up to fourth-order in system-bath coupling, a considerable improvement over the standard quantum master equation techniques. We then numerically corroborate our theory for archetypal settings of linear systems using the exact nonequilibrium Green's function approach. Finally, to demonstrate the advantage of our approach, we deal with the nonlinear spin-boson model to evaluate heat current up to fourth-order and find signatures of cotunnelling process. PMID:25416868

  2. The distribution of pace adopted by cyclists during a cross-country mountain bike World Championships.

    PubMed

    Abbiss, Chris R; Ross, Megan L R; Garvican, Laura A; Ross, Neil; Pottgiesser, Torben; Gregory, John; Martin, David T

    2013-01-01

    The purpose of this study was to examine the distribution of pace self-selected by cyclists of varying ability, biological age and sex performing in a mountain bike World Championship event. Data were collected on cyclists performing in the Elite Male (ELITEmale; n = 75), Elite Female (ELITEfemale; n = 50), Under 23 Male (U23male; n = 62), Under 23 Female (U23female; n = 34), Junior Male (JNRmale; n = 71) and Junior Female (JNRfemale; n = 30) categories of the 2009 UCI Cross-Country Mountain Bike World Championships. Split times were recorded for the top, middle and bottom 20% of all finishers of each category. Timing splits were positioned to separate the course into technical and non-technical, uphill, downhill and rolling/flat sections. Compared with bottom performers, top performers in all male categories (ELITEmale, U23male, JNRmale) maintained a more even pace over the event as evidenced by a significantly lower standard deviation and range in average lap speed. Top performers, males, and ELITEmale athletes spent a lower percentage of overall race time on technical uphill sections of the course, compared with middle and bottom placed finishers, females, and JNRmale athletes, respectively. Better male performers adopt a more even distribution of pace throughout cross-country mountain events. Performance of lower placed finishers, females and JNRmale athletes may be improved by enhancing technical uphill cycling ability. PMID:23521618

  3. Sputter-deposited TiN electrode coatings for superior sensing and pacing performance.

    PubMed

    Schaldach, M; Hubmann, M; Weikl, A; Hardt, R

    1990-12-01

    The sensing and pacing performance of pacemaker electrodes is characterized by the electrochemical properties of the electrode/tissue interface affecting tissue reactions and the kinetics of the ionic exchange. The usually smooth metallic electrode surface results in a high pass filter characteristic. To better match the electrode's filter characteristic to the spectral content of the depolarization signal, various combinations of electrode shape, material and surface structure have been researched. The electrode with sputter-deposited TiN coating presented in this report has been designed to meet the demand for low acute as well as chronic thresholds and superior sensing performance not only with respect to spontaneous activity but also regarding the detection of the evoked response. The clinical results obtained with this electrode prove the excellent pacing and sensing properties resulting from minimized polarization losses and optimized filtering of the signal to be detected, respectively. The acute and chronic clinical advantages over previous concepts are attributed mainly to the biocompatibility of the material used and the microcrystalline surface structure achieved by the coating process. The design concept of the new electrode is presented together with the clinical results obtained. While the advancements in microelectronics and battery technology have certainly formed the basis for the development of pulse generators featuring an ever increasing versatility of functions at the same or even smaller pacemaker dimensions, from a point of view of pacing system performance the development of improved electrode concepts as the one presented must be regarded as equally indispensable. PMID:1704562

  4. Using a Coupled Lake Model with WRF to Improve High-Resolution Regional Climate Simulations

    NASA Astrophysics Data System (ADS)

    Mallard, M.; Bullock, R.; Nolte, C. G.; Alapaty, K.; Otte, T.; Gula, J.

    2012-12-01

    Lakes can play a significant role in regional climate by modifying air masses through fluxes of heat and moisture and by modulating inland extremes in temperature. Representing these effects becomes more important as regional climate modeling efforts employ finer grid spacing in order to simulate smaller scales. The Weather Research and Forecasting (WRF) model does not simulate lakes explicitly. Instead, lake points are treated as ocean points, with sea surface temperatures (SSTs) interpolated from the nearest neighboring ocean point in the driving coarse-scale fields. This can result in substantial errors for inland lakes such as the Great Lakes. Although prescribed lake surface temperatures (LSTs) can be used for retrospective modeling applications, this may not be desirable for applications involving downscaling future climate scenarios from a global climate model (GCM). In such downscaling simulations, lakes that impact the regional climate in the area of interest may not be resolved by the coarser global input fields. Explicitly simulating the LST would allow WRF to better represent interannual variability in regions significantly affected by lakes, and the influence of such variability on temperature and precipitation patterns. Therefore, coupling a lake model to WRF may lead to more reliable assessments of the impacts of extreme events on human health and the environment. We employ a version of WRF coupled to the Freshwater Lake model, FLake (Gula and Peltier 2012). FLake is a 1D bulk lake model which provides updated LSTs and ice coverage throughout the integration. This two-layer model uses a temperature-depth profile which includes a homogeneous mixed layer at the surface and a thermocline below. The shape of the thermocline is assumed, based on past theoretical and observational studies. Therefore, additional variables required for FLake to run are minimal, and it does not require tuning for individual lakes. These characteristics are advantageous for a

  5. Improvement of ethanol production by electrochemical redox coupling of Zymomonas mobilis and Saccharomyces cerevisiae.

    PubMed

    Jeon, Bo Young; Park, Doo Hyun

    2010-01-01

    Zymomonas mobilis was immobilized in a modified graphite felt cathode with neutral red (NR-graphite cathode) and Saccharomyces cerevisiae was cultivated on a platinum plate anode to electrochemically activate ethanol fermentation. Electrochemical redox reaction was induced by 3 approximately 4 volt of electric potential charged to a cathode and an anode. Z. mobilis produced 1.3 approximately 1.5 M of ethanol in the cathode compartment and S. cerevisiae did 1.7 approximately 1.9 M in the anode compartment for 96 hr. The ethanol production by Z. mobilis immobilized in the NR-graphite cathode and S. cerevisiae cultivated on the platinum plate was 1.5 approximately 1.6 times higher than those cultivated in the conventional condition. The electrochemical oxidation potential greatly inhibited ethanol fermentation of Z. mobilis but did not S. cerevisiae. Total soluble protein pattern of Z. mobilis cultivated in the electrochemical oxidation condition was getting simplified in proportion to potential intensity based on SDS-PAGE pattern; however the SDS-PAGE pattern of protein extracted from S. cerevisiae cultivated in both oxidation and reduction condition was not changed. When Z. mobilis culture incubated in the cathode compartment for 24 hr was transferred to S. cerevisiae culture in the anode compartment, 0.8 approximately 0.9 M of ethanol was additionally produced by S. cerevisiae for another 24 hr. Conclusively, total 2.0 approximately 2.1 M of ethanol was produced by the electrochemical redox coupling of Z. mobilis and S. cerevisiae for 48 hr. PMID:20134239

  6. Improved light olefin yield from methyl bromide coupling over modified SAPO-34 molecular sieves.

    PubMed

    Zhang, Aihua; Sun, Shouli; Komon, Zachary J A; Osterwalder, Neil; Gadewar, Sagar; Stoimenov, Peter; Auerbach, Daniel J; Stucky, Galen D; McFarland, Eric W

    2011-02-21

    As an alternative to the partial oxidation of methane to synthesis gas followed by methanol synthesis and the subsequent generation of olefins, we have studied the production of light olefins (ethylene and propylene) from the reaction of methyl bromide over various modified microporous silico-aluminophosphate molecular-sieve catalysts with an emphasis on SAPO-34. Some comparisons of methyl halides and methanol as reaction intermediates in their conversion to olefins are presented. Increasing the ratio of Si/Al and incorporation of Co into the catalyst framework improved the methyl bromide yield of light olefins over that obtained using standard SAPO-34. PMID:21203621

  7. Tropical pacing of Antarctic sea ice increase

    NASA Astrophysics Data System (ADS)

    Schneider, D. P.

    2015-12-01

    One reason why coupled climate model simulations generally do not reproduce the observed increase in Antarctic sea ice extent may be that their internally generated climate variability does not sync with the observed phases of phenomena like the Pacific Decadal Oscillation (PDO) and ENSO. For example, it is unlikely for a free-running coupled model simulation to capture the shift of the PDO from its positive to negative phase during 1998, and the subsequent ~15 year duration of the negative PDO phase. In previously presented work based on atmospheric models forced by observed tropical SSTs and stratospheric ozone, we demonstrated that tropical variability is key to explaining the wind trends over the Southern Ocean during the past ~35 years, particularly in the Ross, Amundsen and Bellingshausen Seas, the regions of the largest trends in sea ice extent and ice season duration. Here, we extend this idea to coupled model simulations with the Community Earth System Model (CESM) in which the evolution of SST anomalies in the central and eastern tropical Pacific is constrained to match the observations. This ensemble of 10 "tropical pacemaker" simulations shows a more realistic evolution of Antarctic sea ice anomalies than does its unconstrained counterpart, the CESM Large Ensemble (both sets of runs include stratospheric ozone depletion and other time-dependent radiative forcings). In particular, the pacemaker runs show that increased sea ice in the eastern Ross Sea is associated with a deeper Amundsen Sea Low (ASL) and stronger westerlies over the south Pacific. These circulation patterns in turn are linked with the negative phase of the PDO, characterized by negative SST anomalies in the central and eastern Pacific. The timing of tropical decadal variability with respect to ozone depletion further suggests a strong role for tropical variability in the recent acceleration of the Antarctic sea ice trend, as ozone depletion stabilized by late 1990s, prior to the most

  8. Multisite Pacing for Cardiac Resynchronization Therapy: Promise and Pitfalls.

    PubMed

    Antoniadis, Antonios P; Behar, Jonathan M; Claridge, Simon; Jackson, Tom; Sohal, Manav; Rinaldi, Christopher Aldo

    2016-07-01

    Cardiac resynchronization therapy (CRT) reduces the morbidity and mortality of patients with symptomatic heart failure and intraventricular conduction delay. However, its clinical outcomes are non-uniform and up to one third of treated patients are subsequently classified as non-responders. Multisite pacing (MSP), i.e. stimulating the myocardium from multiple locations, has emerged as a potential therapeutic option in patients requiring CRT. The rationale for MSP is based on the hypothesis that increasing the pacing locations in the left ventricle results in a more physiologic and coordinated myocardial systole. MSP can be achieved by additional leads in the right or left ventricle but this can lead to high battery drain and more frequent generator replacements. Multipolar left ventricular leads can deliver pacing at multiple sites, and therefore, a single lead can be used for MSP. However, the optimal programming settings and the outcomes of this approach remain yet to be determined. PMID:27216844

  9. Digestion of high rate activated sludge coupled to biochar formation for soil improvement in the tropics.

    PubMed

    Nansubuga, Irene; Banadda, Noble; Ronsse, Frederik; Verstraete, Willy; Rabaey, Korneel

    2015-09-15

    High rate activated sludge (HRAS) is well-biodegradable sludge enabling energy neutrality of wastewater treatment plants via anaerobic digestion. However, even through successful digestion a notable residue still remains. Here we investigated whether this residue can be converted to biochar, for its use as a fertilizer or as a solid fuel, and assessed its characteristics and overall process efficiency. In a first phase, HRAS was anaerobicaly digested under mesophilic conditions at a sludge retention time of 20 days. HRAS digested well (57.9 ± 6.2% VS degradation) producing on average 0.23 ± 0.04 L CH4 per gram VS fed. The digestate particulates were partially air-dried to mimic conditions used in developing countries, and subsequently converted to biochar by fixed-bed slow pyrolysis at a residence time of 15 min and at highest heating temperatures (HHT) of 300 °C, 400 °C and 600 °C. Subsequently, the produced chars were characterized by proximate analysis, CHN-elemental analysis, pH in solution and bomb calorimetry for higher heating value. The yield and volatile matter decreased with increasing HHT while ash content and fixed carbon increased with increasing HHT. The produced biochar showed properties optimal towards soil amendment when produced at a temperature of 600 °C with values of 5.91 wt%, 23.75 wt%, 70.35% on dry basis (db) and 0.44 for volatile matter, fixed carbon, ash content and H/C ratio, respectively. With regard to its use for energy purposes, the biochar represented a lower calorific value than the dried HRAS digestate likely due to high ash content. Based on these findings, it can be concluded that anaerobic digestion of HRAS and its subsequent biochar formation at HHT of 600 °C represents an attractive route for sludge management in tropic settings like in Uganda, coupling carbon capture to energy generation, carbon sequestration and nutrient recovery. PMID:26072019

  10. Is right ventricular mid-septal pacing superior to apical pacing in patients with high degree atrio-ventricular block and moderately depressed left ventricular function?*

    PubMed Central

    Chen, Kang; Mao, Ye; Liu, Shao-hua; Wu, Qiong; Luo, Qing-zhi; Pan, Wen-qi; Jin, Qi; Zhang, Ning; Ling, Tian-you; Chen, Ying; Gu, Gang; Shen, Wei-feng; Wu, Li-qun

    2014-01-01

    Objective: We are aimed to investigate whether right ventricular mid-septal pacing (RVMSP) is superior to conventional right ventricular apical pacing (RVAP) in improving clinical functional capacity and left ventricular ejection fraction (LVEF) for patients with high-degree atrio-ventricular block and moderately depressed left ventricle (LV) function. Methods: Ninety-two patients with high-degree atrio-ventricular block and moderately reduced LVEF (ranging from 35% to 50%) were randomly allocated to RVMSP (n=45) and RVAP (n=47). New York Heart Association (NYHA) functional class, echocardiographic LVEF, and distance during a 6-min walk test (6MWT) were determined at 18 months after pacemaker implantation. Serum levels of N-terminal pro-brain natriuretic peptide (NT-proBNP) were measured using an enzyme-linked immunosorbent assay (ELISA) kit. Results: Compared with baseline, NYHA functional class remained unchanged at 18 months, distance during 6MWT (485 m vs. 517 m) and LVEF (36.7% vs. 41.8%) were increased, but BNP levels were reduced (2352 pg/ml vs. 710 pg/ml) in the RVMSP group compared with those in the RVAP group, especially in patients with LVEF 35%–40% (for all comparisons, P<0.05). However, clinical function capacity and LV function measurements were not significantly changed in patients with RVAP, despite the pacing measurements being similar in both groups, such as R-wave amplitude and capture threshold. Conclusions: RVMSP provides a better clinical utility, compared with RVAP, in patients with high-degree atrioventricular block and moderately depressed LV function whose LVEF levels ranged from 35% to 40%. PMID:24903987

  11. Nanocellulose-based Translucent Diffuser for Optoelectronic Device Applications with Dramatic Improvement of Light Coupling.

    PubMed

    Wu, Wei; Tassi, Nancy G; Zhu, Hongli; Fang, Zhiqiang; Hu, Liangbing

    2015-12-01

    Nanocellulose is a biogenerated and biorenewable organic material. Using a process based on 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)/NaClO/NaBr system, a highly translucent and light-diffusive film consisting of many layers of nanocellulose fibers and wood pulp microfibers was made. The film demonstrates a combination of large optical transmittance of ∼90% and tunable diffuse transmission of up to ∼78% across the visible and near-infrared spectra. The detailed characterizations of the film indicate the combination of high optical transmittance and haze is due to the film's large packing density and microstructured surface. The superior optical properties make the film a translucent light diffuser and applicable for improving the efficiencies of optoelectronic devices such as thin-film silicon solar cells and organic light-emitting devices. PMID:26572592

  12. Primary Endpoints of the Biventricular Pacing after Cardiac Surgery Trial

    PubMed Central

    Spotnitz, Henry M.; Cabreriza, Santos; Wang, Daniel Y.; Quinn, T. Alexander; Cheng, Bin; Bedrosian, Lauren; Aponte-Patel, Linda; Smith, Craig R.

    2013-01-01

    Background To determine whether optimized biventricular pacing increases cardiac index in patients at risk of left ventricular dysfunction after cardiopulmonary bypass. Procedures included coronary artery bypass, aortic or mitral surgery and combinations. This trial was approved by the Columbia University Institutional Review Board and was conducted under an Investigational Device Exemption. Methods Screening of 6,346 patients yielded 47 endpoints. With informed consent, 61 patients were randomized to pacing or control groups. Atrioventricular and interventricular delays were optimized one (Phase I), two (Phase II), and 12–24 hours (Phase III) after bypass in all patients. Cardiac index was measured by thermal dilution in triplicate. Two-sample t-test assessed differences between groups and subgroups. Results Cardiac index was 12% higher (2.83±0.16 (S.E.M.) vs. 2.52±0.13 liters/minute/square meter) in the paced group, less than predicted and not statistically significant (p=0.14). However, when aortic and aortic/mitral surgery groups were combined, cardiac index increased 29% in the paced group (2.90±0.19, n=14) vs. controls (2.24±0.15, n=11) (p=0.0138). Using a linear mixed effects model, t-test revealed that mean arterial pressure increased with pacing vs. no pacing at all optimization points (Phase I 79.2±1.7 vs. 74.5±1.6 mmHg, p=0.008, Phase II 75.9±1.5 vs. 73.6±1.8, p=0.006, Phase III 81.9±2.8 vs. 79.5±2.7, p=0.002) Conclusions Cardiac index did not increase significantly overall but increased 29% after aortic valve surgery. Mean arterial pressure increased with pacing at three time points. Additional studies are needed to distinguish rate from resynchronization effects, emphasize atrioventricular delay optimization, and examine clinical benefits of temporary postoperative pacing. PMID:23866800

  13. The 'death pace' in the CO.17 trial.

    PubMed

    Formica, Vincenzo; Formica, Domenico; Formica, Giovanni

    2016-01-01

    In an era where the cost of care in oncology is rising, suggestions of new frameworks that may help in orienting biomarker discovery are highly desirable. We propose a different perspective for looking at survival data, which we call 'death pace' analysis, which focuses on the variation of the gap between survival curves over time and that may make it easier to identify subpopulations with distinct predictive molecular features. The recently published data on EJC on the impact of the primary colonic site in the CO.17 trial seem to be particularly suitable for the death pace analysis. PMID:26688001

  14. Centrifugal dryers keep pace with the market

    SciTech Connect

    Fiscor, S.

    2008-03-15

    New plant design and upgrades create a shift in dewatering strategies. The article describes recent developments. Three major manufacturers supply centrifugal dryers - TEMA, Centrifugal & Mechanical Industries (CMI) and Ludowici. CMI introduced a line of vertical centrifugal dryers. TEMA improved the techniques by developing a horizontal vibratory centrifuge (HVC) which simplified maintenance. 3 figs., 1 photo.

  15. DiPALS: Diaphragm Pacing in patients with Amyotrophic Lateral Sclerosis - a randomised controlled trial.

    PubMed Central

    McDermott, Christopher J; Bradburn, Mike J; Maguire, Chin; Cooper, Cindy L; Baird, Wendy O; Baxter, Susan K; Cohen, Judith; Cantrill, Hannah; Dixon, Simon; Ackroyd, Roger; Baudouin, Simon; Bentley, Andrew; Berrisford, Richard; Bianchi, Stephen; Bourke, Stephen C; Darlison, Roy; Ealing, John; Elliott, Mark; Fitzgerald, Patrick; Galloway, Simon; Hamdalla, Hisham; Hanemann, C Oliver; Hughes, Philip; Imam, Ibrahim; Karat, Dayalan; Leek, Roger; Maynard, Nick; Orrell, Richard W; Sarela, Abeezar; Stradling, John; Talbot, Kevin; Taylor, Lyn; Turner, Martin; Simonds, Anita K; Williams, Tim; Wedzicha, Wisia; Young, Carolyn; Shaw, Pamela J

    2016-01-01

    BACKGROUND Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease resulting in death, usually from respiratory failure, within 2-3 years of symptom onset. Non-invasive ventilation (NIV) is a treatment that when given to patients in respiratory failure leads to improved survival and quality of life. Diaphragm pacing (DP), using the NeuRx/4(®) diaphragm pacing system (DPS)™ (Synapse Biomedical, Oberlin, OH, USA), is a new technique that may offer additional or alternative benefits to patients with ALS who are in respiratory failure. OBJECTIVE The Diaphragm Pacing in patients with Amyotrophic Lateral Sclerosis (DiPALS) trial evaluated the effect of DP on survival over the study duration in patients with ALS with respiratory failure. DESIGN The DiPALS trial was a multicentre, parallel-group, open-label, randomised controlled trial incorporating health economic analyses and a qualitative longitudinal substudy. PARTICIPANTS Eligible participants had a diagnosis of ALS (ALS laboratory-supported probable, clinically probable or clinically definite according to the World Federation of Neurology revised El Escorial criteria), had been stabilised on riluzole for 30 days, were aged ≥ 18 years and were in respiratory failure. We planned to recruit 108 patients from seven UK-based specialist ALS or respiratory centres. Allocation was performed using 1 : 1 non-deterministic minimisation. INTERVENTIONS Participants were randomised to either standard care (NIV alone) or standard care (NIV) plus DP using the NeuRX/4 DPS. MAIN OUTCOME MEASURES The primary outcome was overall survival, defined as the time from randomisation to death from any cause. Secondary outcomes were patient quality of life [assessed by European Quality of Life-5 Dimensions, three levels (EQ-5D-3L), Short Form questionnaire-36 items and Sleep Apnoea Quality of Life Index questionnaire]; carer quality of life (EQ-5D-3L and Caregiver Burden Inventory); cost-utility analysis and health

  16. Improved energy coupling of human P-glycoprotein by the glycine 185 to valine mutation.

    PubMed

    Omote, Hiroshi; Figler, Robert A; Polar, Mark K; Al-Shawi, Marwan K

    2004-04-01

    A glycine 185 to valine mutation of human P-glycoprotein (ABCB1, MDR1) has been previously isolated from high colchicine resistance cell lines. We have employed purified and reconstituted P-glycoproteins expressed in Saccharomyces cerevisiae [Figler et al. (2000) Arch. Biochem. Biophys. 376, 34-46] and devised a set of thermodynamic analyses to reveal the mechanism of improved resistance. Purified G185V enzyme shows altered basal ATPase activity but a strong stimulation of colchicine- and etoposide-dependent activities, suggesting a tight regulation of ATPase activity by these drugs. The mutant enzyme has a higher apparent K(m) for colchicine and a lower K(m) for etoposide than that of wild type. Kinetic constants for other transported drugs were not significantly modified by this mutation. Systematic thermodynamic analyses indicate that the G185V enzyme has modified thermodynamic properties of colchicine- and etoposide-dependent activities. To improve the rate of colchicine or etoposide transport, the G185V enzyme has lowered the Arrhenius activation energy of the transport rate-limiting step. The high transition state energies of wild-type P-glycoprotein, when transporting etoposide or colchicine, increase the probability of nonproductive degradation of the transition state without transport. G185V P-glycoprotein transports etoposide or colchicine in an energetically more efficient way with decreased enthalpic and entropic components of the activation energy. Our new data fully reconcile the apparently conflicting results of previous studies. EPR analysis of the spin-labeled G185C enzyme in a cysteine-less background and kinetic parameters of the G185C enzyme indicate that position 185 is surrounded by other residues and is volume sensitive. These results and atomic detail structural modeling suggest that residue 185 is a pivotal point in transmitting conformational changes between the catalytic sites and the colchicine drug binding domain. Replacement of this

  17. Mutual coupling of hydrologic and hydrodynamic models - a viable approach for improved large-scale inundation estimates?

    NASA Astrophysics Data System (ADS)

    Hoch, Jannis; Winsemius, Hessel; van Beek, Ludovicus; Haag, Arjen; Bierkens, Marc

    2016-04-01

    Due to their increasing occurrence rate and associated economic costs, fluvial floods are large-scale and cross-border phenomena that need to be well understood. Sound information about temporal and spatial variations of flood hazard is essential for adequate flood risk management and climate change adaption measures. While progress has been made in assessments of flood hazard and risk on the global scale, studies to date have made compromises between spatial resolution on the one hand and local detail that influences their temporal characteristics (rate of rise, duration) on the other. Moreover, global models cannot realistically model flood wave propagation due to a lack of detail in channel and floodplain geometry, and the representation of hydrologic processes influencing the surface water balance such as open water evaporation from inundated water and re-infiltration of water in river banks. To overcome these restrictions and to obtain a better understanding of flood propagation including its spatio-temporal variations at the large scale, yet at a sufficiently high resolution, the present study aims to develop a large-scale modeling tool by coupling the global hydrologic model PCR-GLOBWB and the recently developed hydrodynamic model DELFT3D-FM. The first computes surface water volumes which are routed by the latter, solving the full Saint-Venant equations. With DELFT3D FM being capable of representing the model domain as a flexible mesh, model accuracy is only improved at relevant locations (river and adjacent floodplain) and the computation time is not unnecessarily increased. This efficiency is very advantageous for large-scale modelling approaches. The model domain is thereby schematized by 2D floodplains, being derived from global data sets (HydroSHEDS and G3WBM, respectively). Since a previous study with 1way-coupling showed good model performance (J.M. Hoch et al., in prep.), this approach was extended to 2way-coupling to fully represent evaporation

  18. Characterization and comparison of polysaccharides from Lycium barbarum in China using saccharide mapping based on PACE and HPTLC.

    PubMed

    Wu, Ding-Tao; Cheong, Kit-Leong; Deng, Yong; Lin, Peng-Cheng; Wei, Feng; Lv, Xiao-Jie; Long, Ze-Rong; Zhao, Jing; Ma, Shuang-Cheng; Li, Shao-Ping

    2015-12-10

    Water-soluble polysaccharides from 51 batches of fruits of L. barbarum (wolfberry) in China were investigated and compared using saccharide mapping, partial acid hydrolysis, single and composite enzymatic digestion, followed by polysaccharide analysis by using carbohydrate gel electrophoresis (PACE) analysis and high performance thin layer chromatography (HPTLC) analysis, respectively. Results showed that multiple PACE and HPTLC fingerprints of partial acid and enzymatic hydrolysates of polysaccharides from L. barbarum in China were similar, respectively. In addition, results indicated that β-1,3-glucosidic, α-1,4-galactosiduronic and α-1,5-arabinosidic linkages existed in polysaccharides from L. barbarum collected in China, and the similarity of polysaccharides in L. barbarum collected from different regions of China was pretty high, which are helpful for the improvement of the performance of polysaccharides from L. barbarum in functional/health foods area. Furthermore, polysaccharides from Panax notoginseng, Angelica sinensis, and Astragalus membranaceus var. mongholicus were successfully distinguished from those of L. barbarum based on their PACE fingerprints. These results were beneficial to improve the quality control of polysaccharides from L. barabrum and their products, which suggested that saccharide mapping based on PACE and HPTLC analysis could be a routine approach for quality control of polysaccharides. PMID:26428094

  19. Ecosystem function in waste stabilisation ponds: Improving water quality through a better understanding of biophysical coupling

    NASA Astrophysics Data System (ADS)

    Ghadouani, Anas; Reichwaldt, Elke S.; Coggins, Liah X.; Ivey, Gregory N.; Ghisalberti, Marco; Zhou, Wenxu; Laurion, Isabelle; Chua, Andrew

    2014-05-01

    Wastewater stabilisation ponds (WSPs) are highly productive systems designed to treat wastewater using only natural biological and chemical processes. Phytoplankton, microbial communities and hydraulics play important roles for ecosystem functionality of these pond systems. Although WSPs have been used for many decades, they are still considered as 'black box' systems as very little is known about the fundamental ecological processes which occur within them. However, a better understanding of how these highly productive ecosystems function is particularly important for hydrological processes, as treated wastewater is commonly discharged into streams, rivers, and oceans, and subject to strict water quality guidelines. WSPs are known to operate at different levels of efficiency, and treatment efficiency of WSPs is dependent on physical (flow characteristics and sludge accumulation and distribution) and biological (microbial and phytoplankton communities) characteristics. Thus, it is important to gain a better understanding of the role and influence of pond hydraulics and vital microbial communities on pond performance and WSP functional stability. The main aim of this study is to investigate the processes leading to differences in treatment performance of WSPs. This study uses a novel and innovative approach to understand these factors by combining flow cytometry and metabolomics to investigate various biochemical characteristics, including the metabolite composition and microbial community within WSPs. The results of these analyses will then be combined with results from the characterisation of pond hydrodynamics and hydraulic performance, which will be performed using advanced hydrodynamic modelling and advanced sludge profiling technology. By understanding how hydrodynamic and biological processes influence each other and ecosystem function and stability in WSPs, we will be able to propose ways to improve the quality of the treatment using natural processes, with

  20. Sensitivity improved plasmonic gold nanoholes array biosensor by coupling quantum-dots for the detection of specific biomolecular interactions.

    PubMed

    Niu, Lihong; Cheng, Ke; Wu, Yangqing; Wang, Tian; Shi, Qing; Liu, Dan; Du, Zuliang

    2013-12-15

    In this paper, we focused on the large-scale fabrication of gold nanoholes array capable of supporting surface plasmonic resonance (SPR) via the developed nanosphere lithography (NSL) technique, which could be used as high performance biosensor for the detection of specific streptavidin-biotin interactions. Direct UV-vis absorption mode measurement was used to monitor the SPR peak shift. For the better immobilization of biotin, the surface of gold nanoholes array was functionalized with 3-mercaptopropyl trimethoxysilane (MPTS) and 3-aminopropyl triethoxysilane (APTES). After the streptavidin binding to the biotin, the SPR peak position showed an 11 nm wavelength shift due to the refractive index change caused by the biotin-streptavidin binding. The sealing treatment was performed by using bovine serum albumin (BSA) to eliminate the influences of nonspecific adsorption for more accurate detection. Interestingly, the detection sensitivity of the gold nanoholes array could be further enhanced by coupling the water-soluble CdSe/ZnS quantum dots (QDs), which showed four-fold improvement in detection sensitivity as compared to the gold nanoholes array biosensor without the coupling of QDs. The mechanisms for the enhancement of detection sensitivity were also discussed. This would provide new capabilities for the highly sensitive measurements of biomolecular binding. PMID:23850779

  1. Electrical coupling suppression and transient response improvement for a microgyroscope using ascending frequency drive with a 2-DOF PID controller

    NASA Astrophysics Data System (ADS)

    Cui, J.; Guo, Z. Y.; Yang, Z. C.; Hao, Y. L.; Yan, G. Z.

    2011-09-01

    In this paper, we demonstrate a novel control strategy for the drive mode of a microgyroscope using ascending frequency drive (AFD) with an AGC-2DOF PID controller, which drives a resonator with a modulation signal not at the resonant frequency and senses the vibration signal at the resonant frequency, thus realizing the isolation between the actual mechanical response and electrical coupling signal. This approach holds the following three advantages: (1) it employs the AFD signal instead of the resonant frequency drive signal to excite the gyroscope in the drive direction, suppressing the electrical coupling from the drive electrode to the sense electrode; (2) it can reduce the noise at low frequency and resonant frequency by shifting flicker noise to the high-frequency part; (3) it can effectively improve the performance of the transient response of the closed-loop control with a 2-DOF (degree of freedom) PID controller compared with the conventional 1-DOF PID. The stability condition of the whole loop is investigated by utilizing the averaging and linearization method. The control approach is applied to drive a lateral tuning fork microgyroscope. Test results show good agreement with the theoretical and simulation results. The non-ideal electrical antiresonance peak is removed and the resonant peak height increases by approximately 10 dB over a 400 Hz span with a flicker noise reduction of 30 dB within 100 Hz using AFD. The percent overshoot is reduced from 36.2% (1DOF PID) to 8.95% (2DOF PID, about 75.3% overshoot suppression) with 15.3% improvement in setting time.

  2. Improved Measurement Performance of Inorganic Elements in Coal by Laser-Induced Breakdown Spectroscopy Coupled with Internal Standardization

    NASA Astrophysics Data System (ADS)

    Yao, Shunchun; Xu, Jialong; Bai, Kaijie; Lu, Jidong

    2015-11-01

    Laser-induced breakdown spectroscopy was employed to determine the inorganic elements in coal. To improve the measurement's accuracy and precision, a new internal standardization scheme, which we named changed internal standardization, was compared with the traditional internal standardization and no internal standardization for the analysis of inorganic elements. The new internal standardization scheme used the atomic line of carbon at 247.86 nm and the molecular band of CN at 388.34 nm and C2 at 516.32 nm to normalize the lines of inorganic elements that were distributed in the same spectral channel. The performance of the utilization of the new internal standardization scheme was evaluated using a set of coal samples, including twenty calibration samples and five validation samples. The results show that the coefficients of determination R2 and the slope of calibration models coupled with changed internal standardization are better than that of the calibration models coupled with fixed internal standardization and no internal standardization. Moreover, the measurement accuracy and reproducibility of changed internal standardization for the analysis of five validation samples also yielded further improvement. The results that we obtained suggest that changed internal standardization could compensate for the matrix effects, as well as the influence of the difference in the spectral response of the light collection system. supported by Open Research Fund of State Key Laboratory of Pulsed Power Laser Technology of China (No. SKL2013KF03), National Natural Science Foundation of China (Nos. 51206055, 51476061), the Fundamental Research Funds for the Central Universities of China (No. 2014ZZ0014), the New Star of Pearl River on Science and Technology of Guangzhou, China (No. 2014J2200054), the Key Laboratory of Efficient and Clean Energy Utilization of Guangdong Higher Education Institutes of China (No. KLB10004) and Guangdong Province Key Laboratory of Efficient and

  3. PACE Model Gives Advertising Campaign-Centered Curriculum (Commentary).

    ERIC Educational Resources Information Center

    Thayer, Frank

    1990-01-01

    Describes PACE (Portfolio, Assignments, Content, and Evaluation), an advertising curriculum model in which students work on real advertising campaigns. Explains that students form account groups which locate products needing promotional assistance. Identifies the goals of the curriculum to be competent writing and practical understanding of…

  4. A Self-Paced Instructional Approach for Engineering Descriptive Geometry.

    ERIC Educational Resources Information Center

    Beck, Eugene J.

    These materials, used in a self-paced course in engineering descriptive geometry for freshman and sophomore college-level students, cover three modules: basic spatial relationships; intersections, parallelism, and perpendicularity; and graphic analysis and development. Each module contains five instructional units. Each unit includes a rationale,…

  5. "Set the Pace": Nutrition Education DVD for Head Start Parents

    ERIC Educational Resources Information Center

    Adedze, Pascasie; Orr, Robin A.; Chapman-Novakofski, Karen; Donovan, Sharon M.

    2013-01-01

    Childhood overweight remains a major public health problem and innovative nutrition education programs are still needed. Thus, the "Set the Pace" is a nutrition education DVD for Head Start parents which provides visual nutrition education and physical activities to incorporate in their daily routines. (Contains 1 table.)

  6. Kentucky's Parent and Child Education (PACE) Program. Innovations.

    ERIC Educational Resources Information Center

    Devlin, Kevin M.

    A lack of education is a major cause of poverty among many Kentucky citizens. In 1986, Kentucky's dropout rate was the second highest of the 50 states. That same year, Kentucky established the Parent and Child Education (PACE) Program in an effort to combat the problems of insufficient education and poverty that tend to be perpetuated from…

  7. Curriculum Designs for Tech Prep Clusters. PACE '94.

    ERIC Educational Resources Information Center

    Schoon, Kenneth J., Ed.; Wiles, Clyde A., Ed.

    This booklet contains descriptions of various Tech Prep programs developed by PACE (Promoting Academic Excellence In Mathematics, Science & Technology for Workers of the 21st Century). Each entry includes general program descriptions, curriculum outlines, and course descriptions. The clusters and their specialty areas described in the booklet are:…

  8. Self-Paced Physics, Segments 19-23.

    ERIC Educational Resources Information Center

    New York Inst. of Tech., Old Westbury.

    Five study segments of the Self-Paced Physics Course materials are presented in this fourth problems and solutions book used as a part of student course work. The subject matter is related to electric charges, insulators, Coulomb's law, electric fields, lines of force, solid angles, conductors, motion of charged particles, dipoles, electric flux,…

  9. Microcomputers in Education: A Self-Paced Orientation.

    ERIC Educational Resources Information Center

    Carey, Doris; Carey, Regan

    Designed to serve as a self-paced computer course for education students with no experience using microcomputers, this manual contains instructions for operating an Apple IIe microcomputer, its introductory software, and Bank Street Writer, using the DOS 3.3 System Master. The lessons, which contain illustrations and sample screens, include…

  10. Self-Paced Physics, Segments 11-14.

    ERIC Educational Resources Information Center

    New York Inst. of Tech., Old Westbury.

    Four segments of the Self-Paced Physics Course materials are presented in this problems and solutions book for use as the third part of student course work. The subject-matter topics are related to impulses, inelastic and elastic collisions, two-dimensional collision problems, universal constant of gravitation, gravitational acceleration and…

  11. The Pace of Vocabulary Growth Helps Predict Later Vocabulary Skill

    ERIC Educational Resources Information Center

    Rowe, Meredith L.; Raudenbush, Stephen W.; Goldin-Meadow, Susan

    2012-01-01

    Children vary widely in the rate at which they acquire words--some start slow and speed up, others start fast and continue at a steady pace. Do early developmental variations of this sort help predict vocabulary skill just prior to kindergarten entry? This longitudinal study starts by examining important predictors (socioeconomic status [SES],…

  12. Self-Paced Physics, Segments 32-36.

    ERIC Educational Resources Information Center

    New York Inst. of Tech., Old Westbury.

    Five study segments of the Self-Paced Physics Course materials are presented in this seventh problems and solutions book used as a part of student course work. The content is related to magnetic fields, magnetic moments, forces on charged particles in magnetic fields, electron volts, cyclotron, electronic charge to mass ratio, current-carrying…

  13. Atrioventricular Sequential Pacing for Hypertrophic Cardiomyopathy During Liver Transplantation.

    PubMed

    Ramos, Juan; Pai, Sher-Lu; Perry, Dana K; Blackshear, Joseph L; Aniskevich, Stephen

    2015-10-15

    Hypertrophic cardiomyopathy is a myocardial disorder that carries an increased risk of morbidity and mortality during liver transplantation. We describe the use of atrioventricular sequential pacing, placed preoperatively, to assist with intraoperative management of a patient with severe refractory hypertrophic cardiomyopathy undergoing orthotopic piggyback liver transplantation. We discuss the pathogenesis and treatment of this infrequent but serious comorbidity. PMID:26466305

  14. 42 CFR 460.122 - PACE organization's appeals process.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Section 460.122 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN... which the participant believes that his or her life, health, or ability to regain or maintain maximum... appeal. (3) The PACE organization may extend the 72-hour timeframe by up to 14 calendar days for...

  15. Hardware packet pacing using a DMA in a parallel computer

    DOEpatents

    Chen, Dong; Heidelberger, Phillip; Vranas, Pavlos

    2013-08-13

    Method and system for hardware packet pacing using a direct memory access controller in a parallel computer which, in one aspect, keeps track of a total number of bytes put on the network as a result of a remote get operation, using a hardware token counter.

  16. Professional Acknowledgement for Continuing Education (PACE): General Information Forms.

    ERIC Educational Resources Information Center

    ASMT News, 1974

    1974-01-01

    To provide a central, permanent file of continuing education credits for persons in the field of medical technology, the Professional Acknowledgement for Continuing Education (PACE) program was established by the American Society for Medical Technology. Three different types of units will be recorded: College/University credits, Continuing…

  17. Self-Paced Physics, Segments 28-31.

    ERIC Educational Resources Information Center

    New York Inst. of Tech., Old Westbury.

    Four study segments of the Self-Paced Physics Course materials are presented in this sixth problems and solutions book used as a part of student course work. The subject matter is related to electric currents, current densities, resistances, Ohm's law, voltages, Joule heating, electromotive forces, single loop circuits, series and parallel…

  18. PACES: A Model of Student Well-Being

    ERIC Educational Resources Information Center

    Nelson, Mark D.; Tarabochia, Dawn W.; Koltz, Rebecca L.

    2015-01-01

    School counselors design, deliver, and evaluate comprehensive, developmental school counseling programs that are focused on enhancing student development and success. A model of student well-being, known as PACES, is defined and described that consists of five distinct and interactive domains: physical, affective, cognitive, economic, and social.…

  19. 42 CFR 460.50 - Termination of PACE program agreement.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... the quality of care furnished to participants; or (ii) The PACE organization failed to comply.... (c) Termination due to health and safety risk. CMS or a State administering agency may terminate a... cannot ensure the health and safety of its participants. This determination may result from...

  20. 42 CFR 460.50 - Termination of PACE program agreement.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... the quality of care furnished to participants; or (ii) The PACE organization failed to comply.... (c) Termination due to health and safety risk. CMS or a State administering agency may terminate a... cannot ensure the health and safety of its participants. This determination may result from...

  1. 42 CFR 460.50 - Termination of PACE program agreement.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... the quality of care furnished to participants; or (ii) The PACE organization failed to comply.... (c) Termination due to health and safety risk. CMS or a State administering agency may terminate a... cannot ensure the health and safety of its participants. This determination may result from...

  2. 42 CFR 460.50 - Termination of PACE program agreement.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... the quality of care furnished to participants; or (ii) The PACE organization failed to comply.... (c) Termination due to health and safety risk. CMS or a State administering agency may terminate a... cannot ensure the health and safety of its participants. This determination may result from...

  3. Self-Paced Physics, Segments 24-27.

    ERIC Educational Resources Information Center

    New York Inst. of Tech., Old Westbury.

    Four study segments of the Self-Paced Physics Course materials are presented in this fifth problems and solutions book used as a part of student course work. The subject matter is related to work in electric fields, potential differences, parallel plates, electric potential energies, potential gradients, capacitances, and capacitor circuits.…

  4. Self-Paced Physics, Segments 37-40.

    ERIC Educational Resources Information Center

    New York Inst. of Tech., Old Westbury.

    Four study segments of the Self-Paced Physics Course materials are presented in this eighth problems and solutions book used as a part of course assignments. The content is related to magnetic induction, Faraday's law, induced currents, Lenz's law, induced electromotive forces, time-varying magnetic fields, self-inductance, inductors,…

  5. Basic Library Skills: A Self-Paced Workbook.

    ERIC Educational Resources Information Center

    Tierney, Judith

    This self-paced workbook is designed to introduce college students to the resources and facilities of the library and to providing the knowledge and skills necessary to do basic library research. Two introductory chapters include a library-specific tour with floor plans (the D. Leonard Corgan Library, Wilkes-Barre, Pennsylvania) and information…

  6. The Print and Computer Enlargement System--PACE. Final Report.

    ERIC Educational Resources Information Center

    Morford, Ronald A.

    The Print and Computer Enlargement (PACE) System is being designed as a portable computerized reading and writing system that enables a low-vision person to read regular print and then create and edit text using large-print computerized output. The design goal was to develop a system that: weighed no more than 12 pounds so it could be easily…

  7. Library Skills for Teachers: A Self-Paced Workbook.

    ERIC Educational Resources Information Center

    Mech, Terrence

    Designed to introduce education students to the basic library resources in the field, this self-paced workbook assumes a basic knowledge of the library and its resources. Each section in the eight-chapter workbook discusses a particular type of reference material and sample entries are provided when appropriate. Eleven assignments (two multiple…

  8. Pacing strategies during a cycling time trial with simulated headwinds and tailwinds.

    PubMed

    Atkinson, G; Brunskill, A

    2000-10-01

    increased significantly during the first 8.05 km of the V condition when power outputs were 5% higher than in condition C. Heart rate showed no main effect of pacing strategy (p = 0.80) and the interaction between strategy and race split did not reach statistical significance (p = 0.07). These results suggest that in a 16.1 km time trial with equal 8.05 km headwind and tailwind sections, riders habitually set off too fast in the first few kilometres and will benefit (10 s improvement) from a constant pacing strategy and, to a slightly greater degree (12 s improvement), from a variable (5% +/- mean) pacing strategy in line with the variations in wind direction during the race. Riders should choose a constant power when external conditions are constant, but when there are hilly or variable wind sections in the race, a variable power strategy should be planned. This strategy would be best monitored with 'power-measuring devices' rather than heart rate or subjective feelings as the sensitivity of these variables to small but meaningful changes in power during a race is low. PMID:11083127

  9. Improved Modeling of Land-Atmosphere Interactions using a Coupled Version of WRF with the Land Information System

    NASA Technical Reports Server (NTRS)

    Case, Jonathan L.; LaCasse, Katherine M.; Santanello, Joseph A., Jr.; Lapenta, William M.; Petars-Lidard, Christa D.

    2007-01-01

    The exchange of energy and moisture between the Earth's surface and the atmospheric boundary layer plays a critical role in many hydrometeorological processes. Accurate and high-resolution representations of surface properties such as sea-surface temperature (SST), vegetation, soil temperature and moisture content, and ground fluxes are necessary to better understand the Earth-atmosphere interactions and improve numerical predictions of weather and climate phenomena. The NASA/NWS Short-term Prediction Research and Transition (SPORT) Center is currently investigating the potential benefits of assimilating high-resolution datasets derived from the NASA moderate resolution imaging spectroradiometer (MODIS) instruments using the Weather Research and Forecasting (WRF) model and the Goddard Space Flight Center Land Information System (LIS). The LIS is a software framework that integrates satellite and ground-based observational and modeled data along with multiple land surface models (LSMs) and advanced computing tools to accurately characterize land surface states and fluxes. The LIS can be run uncoupled to provide a high-resolution land surface initial condition, and can also be run in a coupled mode with WRF to integrate surface and soil quantities using any of the LSMs available in LIS. The LIS also includes the ability to optimize the initialization of surface and soil variables by tuning the spin-up time period and atmospheric forcing parameters, which cannot be done in the standard WRF. Among the datasets available from MODIS, a leaf-area index field and composite SST analysis are used to improve the lower boundary and initial conditions to the LIS/WRF coupled model over both land and water. Experiments will be conducted to measure the potential benefits from using the coupled LIS/WRF model over the Florida peninsula during May 2004. This month experienced relatively benign weather conditions, which will allow the experiments to focus on the local and mesoscale

  10. Modeling efforts to improve the Asian Summer Monsoon representation in a coupled ocean-atmosphere tropical-channel model

    NASA Astrophysics Data System (ADS)

    Samson, G.; Masson, S. G.; Durand, F.; Terray, P.; Berthet, S.; Jullien, S.

    2015-12-01

    The Asian Summer Monsoon (ASM) simulated over the 1989-2009 period with a new 0.75° coupled ocean-atmosphere tropical-channel (45°S-45°N) model based on WRF and NEMO models is presented. The model biases are comparable to those commonly found in coupled global coupled models (CGCMs): the Findlater jet is too weak, precipitations are underestimated over India while they are overestimated over South-East Asia and the Maritime Continent. The ASM onset is delayed by several weeks, an error which is also very common in current CGCMs. We show that land surface temperature errors are a major source of the ASM low-level circulation and rainfall biases in our model: a cold bias over the Middle-East region weakens the Findlater jet while a warm bias over India strengthens the monsoon circulation in the Bay of Bengal. To explore the origins of those biases and their relationship with the ASM, a series of sensitivity experiments is presented. First, we show that changing the land surface albedo representation in our model directly influences the ASM characteristics by reducing the cold bias in the Middle-East region. It improves the "heat low" representation, which has direct implication on the Findlater jet strength and precipitation over India. Furthermore, the ASM onset is shifted back by almost one month in agreement with observations. Second, a parameterization of the convective cloud-radiative feedback is introduced in the atmospheric model. It acts to reduce the warm bias present in convective regions such as India and favors the monsoon northward migration. As a consequence, the dry bias is reduced in this region. Finally, horizontal resolution is increased from 0.75° to 0.25° for both oceanic and atmospheric models to assess the sensitivity of the ASM biases to the model resolution. Large-scale model errors persist at higher resolution, but are significantly attenuated. Precipitation is improved in mountainous areas with strong orographic control, but also in

  11. 42 CFR 460.132 - Quality assessment and performance improvement plan.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... AND HUMAN SERVICES (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) Quality Assessment and Performance Improvement § 460.132...

  12. 42 CFR 460.132 - Quality assessment and performance improvement plan.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... AND HUMAN SERVICES (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) Quality Assessment and Performance Improvement § 460.132...

  13. The Views of 920 PACE Project Directors. Report No.5 of the Second National Study of PACE.

    ERIC Educational Resources Information Center

    Fairfax County Schools, Baileys Crossroads, VA. Center for Effecting Educational Change.

    This report consists of a survey and statistical analysis of Projects to Advance Creativity in Education (PACE) as viewed by the 920 project directors in this ESEA Title III program. Discussion centers about (1) characteristics of existing projects, (2) problems encountered, (3) views toward State, local, and Federal agencies, (4) criteria for…

  14. PACE IV: The Developmental Physical Education Curriculum from Theory to Practice (PACE = Positive Approaches to Children's Education).

    ERIC Educational Resources Information Center

    Indiana Univ., Bloomington. Dept. of Kinesiology.

    The purpose of PACE is to bring together individuals who have been responsible for new, innovative, and exciting developmental physical education programs. The following summaries are included: "Literacy in the Gym" (Tami Benham); "Activity Ideas for Fundamental Movement Skill Development" (Thomas H. Green); "Creative Movement Activities: A…

  15. A generic selection system for improved expression and thermostability of G protein-coupled receptors by directed evolution.

    PubMed

    Klenk, Christoph; Ehrenmann, Janosch; Schütz, Marco; Plückthun, Andreas

    2016-01-01

    Structural and biophysical studies as well as drug screening approaches on G protein-coupled receptors (GPCRs) have been largely hampered by the poor biophysical properties and low expression yields of this largest class of integral membrane proteins. Thermostabilisation of GPCRs by introduction of stabilising mutations has been a key factor to overcome these limitations. However, labelled ligands with sufficient affinity, which are required for selective binding to the correctly folded receptor, are often not available. Here we describe a novel procedure to improve receptor expression and stability in a generic way, independent of specific ligands, by means of directed evolution in E. coli. We have engineered a homogenous fluorescent reporter assay that only detects receptors which are correctly integrated into the inner cell membrane and, thus, discriminates functional from non-functional receptor species. When we combined this method with a directed evolution procedure we obtained highly expressing mutants of the neurotensin receptor 1 with greatly improved thermostability. By this procedure receptors with poor expression and/or low stability, for which no ligands or only ones with poor binding properties are available, can now be generated in quantities allowing detailed structural and biophysical analysis. PMID:26887595

  16. On the performance improvement of transmitted Bessel beams emitted from sub-wavelength annular aperture coupled with periodic grating

    NASA Astrophysics Data System (ADS)

    Weng, Chun-Hung; Chung, Ming-Han; Lee, Chih-Kung

    2014-02-01

    The lens spatial resolution and depth of focus depends on the numerical aperture and the incident light beam wavelength. Traditionally, smaller focal spot size also means short depth of focus, which may hinder the system integration advancement. We investigate the possibility to break free the limitation associated with small focal size and short depth of focus. It was discovered by T. W. Ebbesen that periodic aperture on metallic film may improve the transmission and confine the divergent angle of the emitting light beams beyond the prediction of the Bethe's theory. We developed single sub-wavelength annular aperture (SAA) first and then used tapered hollow micro-tube to mimic the function of SAA so as to generate Bessel beam in the far-field region. High aspect ratio microstructures were fabricated using the above-mentioned techniques. In addition, coupling annular aperture and periodic grating to further advance the high aspect ratio fabrication technique was also explored. Firstly, to maximize the transmission in specific wavelength, the pitch of grating was modulated. More specifically, we manipulated the periodic grating to search the maximum transmission efficiency in specific waveband. Secondly, in order to improve the depth of focus, we changed the grating slit width to induce proper phase delay. These studies were all verified by FDTD simulations and some experimental results.

  17. A generic selection system for improved expression and thermostability of G protein-coupled receptors by directed evolution

    PubMed Central

    Klenk, Christoph; Ehrenmann, Janosch; Schütz, Marco; Plückthun, Andreas

    2016-01-01

    Structural and biophysical studies as well as drug screening approaches on G protein-coupled receptors (GPCRs) have been largely hampered by the poor biophysical properties and low expression yields of this largest class of integral membrane proteins. Thermostabilisation of GPCRs by introduction of stabilising mutations has been a key factor to overcome these limitations. However, labelled ligands with sufficient affinity, which are required for selective binding to the correctly folded receptor, are often not available. Here we describe a novel procedure to improve receptor expression and stability in a generic way, independent of specific ligands, by means of directed evolution in E. coli. We have engineered a homogenous fluorescent reporter assay that only detects receptors which are correctly integrated into the inner cell membrane and, thus, discriminates functional from non-functional receptor species. When we combined this method with a directed evolution procedure we obtained highly expressing mutants of the neurotensin receptor 1 with greatly improved thermostability. By this procedure receptors with poor expression and/or low stability, for which no ligands or only ones with poor binding properties are available, can now be generated in quantities allowing detailed structural and biophysical analysis. PMID:26887595

  18. Insulin acutely improves mitochondrial function of rat and human skeletal muscle by increasing coupling efficiency of oxidative phosphorylation.

    PubMed

    Nisr, Raid B; Affourtit, Charles

    2014-02-01

    Insulin is essential for the regulation of fuel metabolism and triggers the uptake of glucose by skeletal muscle. The imported glucose is either stored or broken down, as insulin stimulates glycogenesis and ATP synthesis. The mechanism by which ATP production is increased is incompletely understood at present and, generally, relatively little functional information is available on the effect of insulin on mitochondrial function. In this paper we have exploited extracellular flux technology to investigate insulin effects on the bioenergetics of rat (L6) and human skeletal muscle myoblasts and myotubes. We demonstrate that a 20-min insulin exposure significantly increases (i) the cell respiratory control ratio, (ii) the coupling efficiency of oxidative phosphorylation, and (iii) the glucose sensitivity of anaerobic glycolysis. The improvement of mitochondrial function is explained by an insulin-induced immediate decrease of mitochondrial proton leak. Palmitate exposure annuls the beneficial mitochondrial effects of insulin. Our data improve the mechanistic understanding of insulin-stimulated ATP synthesis, and reveal a hitherto undisclosed insulin sensitivity of cellular bioenergetics that suggests a novel way of detecting insulin responsiveness of cells. PMID:24212054

  19. Improving the spatial resolution of soft X-ray detection using an Electron-Multiplying Charge-Coupled Device

    NASA Astrophysics Data System (ADS)

    Soman, M. R.; Hall, D. J.; Tutt, J. H.; Murray, N. J.; Holland, A. D.; Schmitt, T.; Raabe, J.; Schmitt, B.

    2013-01-01

    The Super Advanced X-ray Emission Spectrometer (SAXES) is an instrument at the Swiss Light Source designed for Resonant Inelastic X-ray Scattering with an energy resolution (E/ΔE) better than 12000 at 930 eV. Improvements to the instrument have been predicted that could allow the energy resolution to be improved by a factor of two. To achieve this, the spatial resolution of the detector (currently a Charge-Coupled Device, CCD) over which the energy spectrum is dispersed would have to be improved to better than 5 μm. X-ray photons with energies between a few hundred to a few thousand electron volts primarily interact within the field-free region of back-illuminated CCDs, where each photon forms an electron cloud that diffuses isotropically before reaching the depleted region close to the electrodes. Each photon's electron cloud is likely to be detected as an event with signal split across multiple pixels. Analysing these split events using centroiding techniques allows the photon's interaction position to be determined to a sub-pixel level. PolLux is a soft X-ray microspectroscopy endstation at the Swiss Light Source that can focus 200 eV to 1200 eV X-rays to a spot size of approximately 20 nm. Previous studies using data taken with a linear scan across the centre of a pixel in 3 μm steps predicted an improved resolution by applying centroiding techniques and using an Electron-Multiplying CCD (EM-CCD). In this study, a full 2D map of the centroiding accuracy in the pixel is presented, formed by rastering in two dimensions across the image plane in single micron steps. The improved spatial resolution from centroiding events in the EM-CCD in all areas of the pixel over the standard CCD is attributed to the improved signal to noise ratio provided by the multiplication register even at high pixel readout speeds (tens of MHz).

  20. A self-paced oral feeding system that enhances preterm infants’ oral feeding skills

    PubMed Central

    Lau, C; Fucile, S; Schanler, RJ

    2014-01-01

    Aim Very low birth weight (VLBW) infants have difficulty transitioning to independent oral feeding, be they breast- or bottle-feeding. We developed a ‘self-paced’ feeding system that eliminates the natural presence of the positive hydrostatic pressure and internal vacuum build-up within a bottle during feeding. Such system enhanced these infants’ oral feeding performance as monitored by overall transfer (OT; % ml taken/ml prescribed), rate of transfer (RT; ml/min over an entire feeding). This study hypothesizes that the improvements observed in these infants resulted from their ability to use more mature oral feeding skills (OFS). Methods ‘Feeders and growers’ born between 26–29 weeks gestation were assigned to a control or experimental group fed with a standard or self-paced bottle, respectively. They were monitored when taking 1–2 and 6–8 oral feedings/day. OFS was monitored using our recently published non-invasive assessment scale that identifies 4 maturity levels based on infants’ RT and proficiency (PRO; % ml taken during the first 5 min of a feeding/total ml prescribed) during bottle feeding. Results Infants oral feeding outcomes, i.e., OT, RT, PRO, and OFS maturity levels were enhanced in infants fed with the self-paced vs. standard bottle (p ≤ 0.007). Conclusion The improved oral feeding performance of VLBW infants correlated with enhanced OFS. This study is a first to recognize that VLBW infants’ true OFS are more mature than recognized. We speculate that the physical properties inherent to standard bottles that are eliminated with the self-paced system interfere with the display of their true oral feeding potential thereby hindering their overall oral feeding performance. PMID:25999776

  1. Improve the Strength of PLA/HA Composite Through the Use of Surface Initiated Polymerization and Phosphonic Acid Coupling Agent

    PubMed Central

    Wang, Tongxin; Chow, Laurence C.; Frukhtbeyn, Stanislav A.; Ting, Andy Hai; Dong, Quanxiao; Yang, Mingshu; Mitchell, James W.

    2011-01-01

    Bioresorbable composite made from degradable polymers, e.g., polylactide (PLA), and bioactive calcium phosphates, e.g., hydroxyapatite (HA), are clinically desirable for bone fixation, repair and tissue engineering because they do not need to be removed by surgery after the bone heals. However, preparation of PLA/HA composite from non-modified HA usually results in mechanical strength reductions due to a weak interface between PLA and HA. In this study, a calcium-phosphate/phosphonate hybrid shell was developed to introduce a greater amount of reactive hydroxyl groups onto the HA particles. Then, PLA was successfully grafted on HA by surface-initiated polymerization through the non-ionic surface hydroxyl groups. Thermogravimetric analysis indiated that the amount of grafted PLA on HA can be up to 7 %, which is about 50 % greater than that from the literature. PLA grafted HA shows significantly different pH dependent ζ-potential and particle size profiles from those of uncoated HA. By combining the phosphonic acid coupling agent and surface initiated polymerization, PLA could directly link to HA through covalent bond so that the interfacial interaction in the PLA/HA composite can be significantly improved. The diametral tensile strength of PLA/HA composite prepared from PLA-grafted HA was found to be over twice that of the composite prepared from the non-modified HA. Moreover, the tensile strength of the improved composite was 23 % higher than that of PLA alone. By varying additional variables, this approach has the potential to produce bioresorbable composites with improved mechanical properties that are in the range of natural bones, and can have wide applications for bone fixation and repair in load-bearing areas. PMID:22399838

  2. 42 CFR 460.150 - Eligibility to enroll in a PACE program.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... SERVICES (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) Participant Enrollment and Disenrollment § 460.150 Eligibility to enroll in...

  3. 42 CFR 460.150 - Eligibility to enroll in a PACE program.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... SERVICES (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) Participant Enrollment and Disenrollment § 460.150 Eligibility to enroll in...

  4. 42 CFR 460.150 - Eligibility to enroll in a PACE program.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... SERVICES (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) Participant Enrollment and Disenrollment § 460.150 Eligibility to enroll in...

  5. 42 CFR 460.150 - Eligibility to enroll in a PACE program.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... SERVICES (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) Participant Enrollment and Disenrollment § 460.150 Eligibility to enroll in...

  6. Effects of pacing magnitudes and forms on bistability width in a modeled ventricular tissue

    NASA Astrophysics Data System (ADS)

    Huang, Xiaodong; Liu, Xuemei; Zheng, Lixian; Mi, Yuanyuan; Qian, Yu

    2013-07-01

    Bistability in periodically paced cardiac tissue is relevant to cardiac arrhythmias and its control. In the present paper, one-dimensional tissue of the phase I Luo-Rudy model is numerically investigated. The effects of various parameters of pacing signals on bistability width are studied. The following conclusions are obtained: (i) Pacing can be classified into two types: pulsatile and sinusoidal types. Pulsatile pacing reduces bistability width as its magnitude is increased. Sinusoidal pacing increases the width as its amplitude is increased. (ii) In a pacing period the hyperpolarizing part plays a more important role than the depolarizing part. Variations of the hyperpolarizing ratio in a period evidently change the width of bistability and its variation tendency. (iii) A dynamical mechanism is proposed to qualitatively explain the phenomena, which reveals the reason for the different effects of pulsatile and sinusoidal pacing on bistability. The methods for changing bistability width by external pacing may help control arrhythmias in cardiology.

  7. Lunar plasma measurement by MAP-PACE onboard KAGUYA (SELENE)

    NASA Astrophysics Data System (ADS)

    Saito, Yoshifumi

    Low energy charged particles around the Moon were vigorously observed by Moon orbiting satellites and plasma instrumentation placed on the lunar surface in 1960s and 1970s. Though there were some satellites that explored the Moon afterwards, most of them were dedicated to the global mapping of the lunar surface. KAGUYA(SELENE) is a Japanese lunar orbiter that studies the origin and evolution of the Moon by means of global mapping of element abundances, mineralogical composition, and surface geographical mapping from 100km altitude. KAGUYA was successfully launched on 14 September 2007 by HIIA launch vehicle from Tanegashima Space Center in Japan. KAGUYA was inserted into a circular lunar polar orbit of 100km altitude and started continuous observation in mid-December 2007. One of the fourteen science instruments MAP-PACE (MAgnetic field and Plasma experiment - Plasma energy Angle and Composition Experiment) was developed for the comprehensive three-dimensional plasma measurement around the Moon. MAP-PACE consists of 4 sensors: ESA (Electron Spectrum Analyzer)-S1, ESA-S2, IMA (Ion Mass Analyzer), and IEA (Ion Energy Analyzer). ESA-S1 and S2 measure the distribution function of low energy electrons below 15keV. IMA and IEA measure the distribution function of low energy ions below 28keV/q. IMA has an ability to discriminate the ion mass with high mass resolution. PACE sensors have been measuring solar wind, plasmas in the wake region of the Moon and plasmas in the Earth's magnetosphere. ESA sensors have discovered electron heating over magnetic anomalies on the lunar surface. ESA sensors have also observed electrons accelerated from the lunar surface in the wake region. PACE ion sensors have discovered new features of low energy ions around the Moon. IMA has discovered the existence of alkali ions that are originated from the lunar surface or lunar atmosphere and are picked up by the solar wind. IEA and IMA sensors discovered solar wind reflection by the Moon. PACE

  8. Effects of surface treatment with coupling agents of PVDF-HFP fibers on the improvement of the adhesion characteristics on PDMS

    NASA Astrophysics Data System (ADS)

    Kwon, O. M.; See, S. J.; Kim, S. S.; Hwang, H. Y.

    2014-12-01

    Surface treatment of polyvinylidene fluoride-co-hexafluoropropylene (PVDF-HFP) fibers was conducted with coupling agents such as epoxy silane, amino silane, and titanate to improve the adhesion characteristics of PVDF-HFP fibers and polydimethylsiloxane (PDMS). The adhesion strength was largest when 4 wt% amino silane was used for surface treatment, showing a 250% improvement compared to the untreated case. Surface roughening and shrinking of the PVDF-HFP fibers were observed after surface treatment, but no chemical bonding occurred between the PVDF-HFP fibers and the coupling agents. It was thus concluded that the improvement of the adhesion characteristics of the PVDF-HFP fibers and PDMS was caused by the physical bonding between them due to the surface treatment with coupling agents. In addition, for the surface roughening mechanism, amino silane infiltration into the PVDF-HFP fibers during the surface treatment, followed by extraction during the drying process, was suggested.

  9. Changes in Mood in New Enrollees at a Program of All-Inclusive Care for the Elderly (PACE)

    PubMed Central

    Seaton, Stephanie M.; Sutcliffe, Siobhan; Austin, Shane

    2015-01-01

    OBJECTIVES To examine changes in mood after 9 months of enrollment in a Program of All- Inclusive Care for the Elderly (PACE). DESIGN Cohort Study SETTING Alexian Brothers PACE–St. Louis, Missouri PARTICIPANTS Newly enrolled patients aged 55 or older, living in the PACE service area, eligible for nursing home care, and able to live safely in the community with continuous care for at least 9 months (n=182). MAIN OUTCOME MEASURES Geriatric Depression Scale (GDS)-15 score at the pre- admission evaluation (PAE) and the 9 month evaluation (9ME). RESULTS Of the 182 patients evaluated, 27% (n=49) met the definition of depression as defined by the GDS-15 score of ≥6 at the PAE. At the 9ME, only 11% of patients met the depression criteria (p<0.001). Of the patients who met the criteria for depression at the PAE, 80% of patients (n=39) no longer met this criteria at the 9ME (p=0.029). Similar findings were observed by age, sex, and race. Greater improvement was observed among those who were depressed at the PAE; the depressed cohort improved by 5.0 points (p<0.001) on the GDS-15 scale from the PAE to the 9ME, whereas the non-depressed cohort improved by 0.6 points (p=0.003). CONCLUSION The use of PACE as an alternative intervention may be a good option to improve mood in older adults. PMID:26260643

  10. The Pacing Board: A Technique to Assist the Transition from Single Word to Multiword Utterances.

    ERIC Educational Resources Information Center

    Kumin, Libby; And Others

    1995-01-01

    Pacing boards can assist in the transition from single word to multiword utterances by children with language impairments. The pacing board provides visual and motor cues to help young children imitate and spontaneously produce multiword utterances as well as increase metalinguistic awareness of speech units. Instructions for making pacing boards…

  11. Effects of Modality and Pace on Achievement, Mental Effort, and Positive Affect in Multimedia Learning Environments

    ERIC Educational Resources Information Center

    Izmirli, Serkan; Kurt, Adile Askim

    2016-01-01

    The purpose of the study was to examine the effects of instruction given with different multimedia modalities (written text + animation or narration + animation) on the academic achievement, cognitive load, and positive affect in different paces (learner-paced or system-paced); 97 freshmen university students divided into four groups taught in…

  12. Society for the Teaching of Psychology and the University of Wisconsin-Milwaukee: U-Pace

    ERIC Educational Resources Information Center

    EDUCAUSE, 2014

    2014-01-01

    The Society for the Teaching of Psychology and the University of Wisconsin-Milwaukee (UWM) partnered to disseminate U-Pace, a technology-enabled instructional model that promotes student success through deeper learning. UWM developed U-Pace in 2006 for an Introduction to Psychology course and, over time, evidence indicates that U-Pace not only…

  13. What Pace Is Best? Assessing Adults' Learning from Slideshows and Video

    ERIC Educational Resources Information Center

    Sage, Kara

    2014-01-01

    When acquiring information from a 2D platform, self-control and/or optimal pacing may help reduce cognitive load and enhance learning outcomes. In the present research, adults viewed novel action sequences via one of four learning media: (1) self-paced slideshows, where viewers advanced through slides at their own pace by clicking a mouse, (2)…

  14. Factors affecting the regulation of pacing: current perspectives

    PubMed Central

    Mauger, Alexis R

    2014-01-01

    During prolonged dynamic and rhythmic exercise, muscular pain and discomfort arises as a result of an increased concentration of deleterious metabolites. Sensed by peripheral nociceptors and transmitted via afferent feedback to the brain, this provides important information regarding the physiological state of the muscle. These sensations ultimately contribute to what is termed “exercise-induced pain”. Despite being well recognized by athletes and coaches, and suggested to be integral to exercise performance, this construct has largely escaped attention in experimental work. This perspective article highlights the current understanding of pacing in endurance performance, and the causes of exercise-induced pain. A new perspective is described, which proposes how exercise-induced pain may be a contributing factor in helping individuals to regulate their work rate during exercise and thus provides an important construct in pacing. PMID:25228823

  15. Optimal pacing for running 400- and 800-m track races

    NASA Astrophysics Data System (ADS)

    Reardon, James

    2013-06-01

    We present a toy model of anaerobic glycolysis that utilizes appropriate physiological and mathematical consideration while remaining useful to the athlete. The toy model produces an optimal pacing strategy for 400-m and 800-m races that is analytically calculated via the Euler-Lagrange equation. The calculation of the optimum v(t) is presented in detail, with an emphasis on intuitive arguments in order to serve as a bridge between the basic techniques presented in undergraduate physics textbooks and the more advanced techniques of control theory. Observed pacing strategies in 400-m and 800-m world-record races are found to be well-fit by the toy model, which allows us to draw a new physiological interpretation for the advantages of common weight-training practices.

  16. Single lead atrial synchronous ventricular pacing: a dream come true.

    PubMed

    Antonioli, G E

    1994-09-01

    Single lead, atrial synchronous pacing systems were developed in the late 1970s. Clinical experience has demonstrated the need to position the "floating" atrial electrode in the mid-to-high right atrium and the need for a specially designed pulse generator (with very high atrial sensitivity) to provide a high quality and amplitude atrial electrogram for consistent sensing. A 12-year experience with different electrode configurations, from the first unipolar designed in 1980 to the most recent atrial bipolar electrodes, has confirmed the validity of the original concept and the long-term reliability of the single lead atrial synchronous pacing system, which can reliably produce long-term atrial sensing and ventricular stimulation in the presence of normal sinoatrial function. PMID:7991425

  17. Chronic animal testing of new cardiac pacing electrodes.

    PubMed

    Adler, S; Spehr, P; Allen, J; Block, W

    1990-12-01

    To evaluate the electrical performance of new electrode technologies, 24 leads containing either carbon coated porous titanium (BIOPORE, (Intermedics, Inc., Freeport, TX], iridium oxide (IROX), or iridium oxide coated with polyethylene glycol (IROX-PEG) electrodes (eight of each) were implanted into the ventricles of 12 canines. Stimulation threshold data was measured at regular intervals for 24 weeks. Low acute values were observed for all leads (0.32 +/- .13 V at 0.6 msec pulse width), but the IROX-PEG electrode demonstrated lower subchronic, peak, and chronic values. Compared to implant, the IROX-PEG electrodes' stimulation thresholds rose only 0.23 V when chronic conditions occurred. There were no significant differences between the electrodes in pacing impedance or R wave amplitude measurements. We conclude that both IROX and IROX-PEG technologies represent a promising approach to the design of more efficient cardiac pacing leads. PMID:1704563

  18. Hemodynamic importance of preserving the normal sequence of ventricular activation in permanent cardiac pacing.

    PubMed

    Leclercq, C; Gras, D; Le Helloco, A; Nicol, L; Mabo, P; Daubert, C

    1995-06-01

    Pacing the right ventricle in the apex profoundly modifies the sequence of activation and thus the sequence of contraction and relaxation of the left ventricle. To evaluate the relative importance of preserving normal ventricular activation sequence and optimal atrioventricular (AV) synchrony in permanent pacing, we compared the effects of three pacing modes: AAI, preserving both normal AV synchrony and normal activation sequence; DDD, with complete ventricular capture that preserves only AV synchrony; and VVI, disrupting both, at rest and during exercise. Hemodynamic and radionuclide studies were performed in 11 patients who had normal intrinsic conduction and who were implanted on a long-term basis with a DDDR pacemaker for isolated sinus node dysfunction. AAI versus DDD and VVI significantly increased cardiac output at rest (6.6 +/- 1.3 L/min vs 6 +/- 0.9 L/min vs 5 +/- 1 L/min; p < 0.01) and during exercise (13.5 +/- 2 L/min vs 12.1 +/- 2.2 L/min vs 14.4 +/- 2.1 L/min; p < 0.01). Pulmonary capillary wedge pressure was lowest with AAI (15.4 +/- 4.5 mm Hg), with an average reduction of 17% compared with DDD (19.6 +/- 5 mm Hg; p < 0.01) and of 30% compared with VVI (25.8 +/- 7 mm Hg; p < 0.01) during exercise. Identical benefits were observed for all other hemodynamic parameters: right atrial pressure, pulmonary artery pressure, left ventricular (LV) stroke work index, and systemic vascular resistances. LV ejection fraction was significantly higher in AAI than in DDD at rest (61% vs 58%, respectively; p < 0.05) and during exercise (65% vs 60%, respectively; p < 0.05). This improvement in LV systolic function resulted principally from the increase in septal ejection fraction. LV filling also was improved in AAI as demonstrated by a significant increase in peak filling rate at rest and during exercise. These data show the importance of preserving, whenever possible, not only normal AV synchrony but also normal ventricular activation sequence in permanent cardiac

  19. Improving Ground Motion Simulation Capabilities for Underground Explosion Monitoring: Coupling Hydrodynamic-To Solvers and Studies of Emplacement Conditions

    NASA Astrophysics Data System (ADS)

    Xu, H.; Rodgers, A.; Lomov, I.; Petersson, A.; Sjogreen, B.; Vorobiev, O.; Chipman, V.

    2011-12-01

    We report research being performed to improve underground nuclear explosion (UNE) monitoring by developing capabilities for hydrodynamic modeling of ground motions. This effort involves work along two thrusts: 1) we are coupling hydrodynamic (non-linear shock) and seismic (linear anelastic) wave propagation codes; and 2) we are investigating the effect of source emplacement conditions on ground motions in the near field due to nonlinearity and comparing with the empirical models. For both thrusts we are modeling explosion motions using GEODYN, a fully three-dimensional Eulerian hydrodynamic code developed at LLNL. This code incorporates many important features for modeling shock waves in geologic materials, including non-linear response (e.g. porosity, tensile failure, yielding), topography, gravity, 3D material heterogeneities and adaptive mesh refinement. The calculation accuracy is well validated with the analytical solutions to the Lamb's problem and to the finite dilatational volume source at depth in a linear elastic medium. In order to propagate full waveform solutions from hydrodynamic simulations to distances where seismic measurements are made we are coupling GEODYN to WPP (LLNL's anelastic finite difference code for seismic wave simulation). Complex motions computed by GEODYN for explosions are recorded on a dense grid spanning the ranges where motions become linear (elastic). These wavefield records are processed and embedded into the WPP domain where they are introduced as a boundary driving source and continue to propagate as elastic waves at much lower numerical cost than with nonlinear GEODYN. The coupling scheme is validated by comparing the analytical, direct GEODYN solutions and WPP solutions to the finite dilatational volume source at depth in a linear elastic medium, and also by comparing the direct GEODYN solutions and WPP solutions to a complex 1kt chemical explosion in nonlinear granite at stations beyond the elastic radius. The excellent

  20. Solar thermal electricity in 1998: An IEA/SolarPACES summary of status and future prospects

    SciTech Connect

    Tyner, C.E.; Kolb, G.J.; Meinecke, W.; Trieb, F.

    1998-07-01

    Research and development activities sponsored by countries within the International Energy Agency`s solar thermal working group. SolarPACES, have helped reduce the cost of solar thermal systems to one-fifth that of the early pilot plants. Continued technological improvements are currently being proven in next-generation demonstration plants. These advances, along with cost reductions made possible by scale-up to larger production and construction of a succession of power plants, have made solar thermal systems the lowest-cost solar energy in the world and promise cost-competitiveness with fossil-fuel plants in the future. Solar thermal technologies are appropriate for a wide range of applications, including dispatchable central-station power plants where they can meet peak-load to near-base-load needs of a utility, and distributed, modular power plants for both remote and grid-connected applications. In this paper, the authors present the collective position of the SolarPACES community on solar electricity-generating technology. They discuss the current status of the technology and likely near-term improvements; the needs of target markets; and important technical and financial issues that must be resolved for success in near-term global markets.

  1. Environmental Coupling Modulates the Attractors of Rhythmic Coordination

    ERIC Educational Resources Information Center

    Kudo, Kazutoshi; Park, Hyeonsaeng; Kay, Bruce A.; Turvey, M. T.

    2006-01-01

    A simple instance of coupling behavior to the environment is oscillating the hands in pace with metronome beats. This environmental coupling can be weaker (1 beat per cycle) or stronger (2 beats per cycle). The authors examined whether strength of environmental coupling enhanced the stability of in-phase bimanual coordination. Detuning by…

  2. Coupling Gd‑DTPA with a bispecific, recombinant protein anti‑EGFR‑iRGD complex improves tumor targeting in MRI.

    PubMed

    Xin, Xiaoyan; Sha, Huizi; Shen, Jingtao; Zhang, Bing; Zhu, Bin; Liu, Baorui

    2016-06-01

    Recombinant anti‑epidermal growth factor receptor‑internalizing arginine‑glycine‑aspartic acid (anti‑EGFR single‑domain antibody fused with iRGD peptide) protein efficiently targets the EGFR extracellular domain and integrin αvβ/β5, and shows a high penetration into cells. Thus, this protein may improve penetration of conjugated drugs into the deep zone of gastric cancer multicellular 3D spheroids. In the present study, a novel tumor‑targeting contrast agent for magnetic resonance imaging (MRI) was developed, by coupling gadolinium‑diethylene triamine pentaacetate (Gd‑DTPA) with the bispecific recombinant anti‑EGFR‑iRGD protein. The anti‑EGFR‑iRGD protein was extracted from Escherichia coli and Gd was loaded onto the recombinant protein by chelation using DTPA anhydride. Single‑targeting agent anti‑EGFR‑DTPA‑Gd, which served as the control, was also prepared. The results of the present study showed that anti‑EGFR‑iRGD‑DTPA‑Gd exhibited no significant cyto-toxicity to human gastric carcinoma cells (BGC‑823) under the experimental conditions used. Compared with a conventional contrast agent (Magnevist), anti‑EGFR‑iRGD‑DTPA‑Gd showed higher T1 relaxivity (10.157/mM/sec at 3T) and better tumor‑targeting ability. In addition, the signal intensity and the area under curve for the enhanced signal time in tumor, in vivo, were stronger than Gd‑DTPA alone or the anti‑EGFR‑Gd control. Thus, Gd‑labelled anti‑EGFR‑iRGD has potential as a tumor‑targeting contrast agent for improved MRI. PMID:27035336

  3. Coupling Gd-DTPA with a bispecific, recombinant protein anti-EGFR-iRGD complex improves tumor targeting in MRI

    PubMed Central

    XIN, XIAOYAN; SHA, HUIZI; SHEN, JINGTAO; ZHANG, BING; ZHU, BIN; LIU, BAORUI

    2016-01-01

    Recombinant anti-epidermal growth factor receptor-internalizing arginine-glycine-aspartic acid (anti-EGFR single-domain antibody fused with iRGD peptide) protein efficiently targets the EGFR extracellular domain and integrin αvβ/β5, and shows a high penetration into cells. Thus, this protein may improve penetration of conjugated drugs into the deep zone of gastric cancer multicellular 3D spheroids. In the present study, a novel tumor-targeting contrast agent for magnetic resonance imaging (MRI) was developed, by coupling gadolinium-diethylene triamine pentaacetate (Gd-DTPA) with the bispecific recombinant anti-EGFR-iRGD protein. The anti-EGFR-iRGD protein was extracted from Escherichia coli and Gd was loaded onto the recombinant protein by chelation using DTPA anhydride. Single-targeting agent anti-EGFR-DTPA-Gd, which served as the control, was also prepared. The results of the present study showed that anti-EGFR-iRGD-DTPA-Gd exhibited no significant cyto toxicity to human gastric carcinoma cells (BGC-823) under the experimental conditions used. Compared with a conventional contrast agent (Magnevist), anti-EGFR-iRGD-DTPA-Gd showed higher T1 relaxivity (10.157/mM/sec at 3T) and better tumor-targeting ability. In addition, the signal intensity and the area under curve for the enhanced signal time in tumor, in vivo, were stronger than Gd-DTPA alone or the anti-EGFR-Gd control. Thus, Gd-labelled anti-EGFR-iRGD has potential as a tumor-targeting contrast agent for improved MRI. PMID:27035336

  4. Mediterranean fluvial response to long-term Quaternary climate change: Improving chronologies by coupling OSL and U-series techniques

    NASA Astrophysics Data System (ADS)

    Candy, Ian; Pope, Richard

    2010-05-01

    Many studies have attempted to understand the relationship between Late Quaternary climate change and Mediterranean river activity over the last 200,000 years (Macklin et al., 2002). The long-terrace records associated with most large river systems and the thick aggradation of fan sediments associated with smaller catchments in southern Europe and north Africa make the Mediterranean an ideal region to test this relationship. Such studies have been further enhanced by recent improvements in optically stimulated luminescence (OSL) and U-series dating techniques which are widely applicable in this region. Despite the fact that combining these two techniques provides the best potential method for constructing high precision chronologies this has rarely been done. In this paper we discuss the problems and advantages of producing "coupled" chronologies with reference to examples from southern Spain and Crete. In both of these examples the use of U-series and OSL dating has allowed the age of terrace aggradation and terrace abandonment (incision) to be constrained, consequently our understanding of fluvial "response" is greatly improved. The paper concludes by discussing further problems in terms of constructing fluvial chronologies which need to be considered and the problems of understanding the climate history of the region in which the catchment is found. Macklin, M.G., Fuller, I.C., Lewin, J., Maas, G.S., Passmore, D.G., Rose, J., Woodward, J.C., Black, S., Hamlin, R.H.B., Rowan, J.S., 2002. Correlation of fluvial sequences in the Mediterranean basin over the last 200 ka and their relationship to climate change. Quaternary Science Reviews, 21, 1633 - 1641.

  5. Fabrication of Silicon Backshorts with Improved Out-of-Band Rejection for Waveguide-Coupled Superconducting Detectors

    NASA Technical Reports Server (NTRS)

    Crowe, Erik J.; Bennett, Charles L.; Chuss, David T.; Denis, Kevin L.; Eimer, Joseph; Lourie, Nathan; Marriage, Tobias; Moseley, Samuel H.; Rostem, Karwan; Stevenson, Thomas R.; Towner, Deborah; U-yen, Kongpop; Wollack, Edward J.

    2012-01-01

    The Cosmology Large Angular Scale Surveyor (CLASS) is a ground-based instrument that will measure the polarization of the cosmic microqave background to search for gravitational waves form a posited epoch of inflation early in the universe's history. This measurement will require integration of superconducting transition-edge sensors with microwave waveguide inputs with good conrol of systematic errors, such as unwanted coupling to stray signals at frequencies outside of a precisely defined microwave band. To address these needs we will present work on the fabrication of silicon quarter-wave backshorts for the CLASS 40GHz focal plane. The 40GHz backshort consists of three degeneratively doped silicon wafers. Two spacer wafers are micromachined with through wafer vins to provide a 2.0mm long square waveguide. The third wafer acts as the backshort cap. The three wafers are bonded at the wafer level by Au-Au thermal compression bonding then aligned and flip chip bonded to the CLASS detector at the chip level. The micromachining techniques used have been optimized to create high aspect ratio waveguides, silicon pillars, and relief trenches with the goal of providing improved out of band signal rejection. We will discuss the fabrication of integrated CLASS superconducting detectors with silicon quarter wave backshorts and present current measurement results.

  6. Improvement of Vacuum Pressure in the Annular-Ring Coupled Structures for the J-PARC Linac

    NASA Astrophysics Data System (ADS)

    Ao, Hiroyuki; Nemoto, Yasuo; Oozone, Akira; Tamura, Jun

    The accelerating cavities of the J-PARC linac, additionally comprising an annular-ring-coupled structure (ACS), went into operation in 2014. To further improve the vacuum pressure of the ACS, an additional nonevaporable getter (NEG) pump was designed so that it could be installed independent of the vacuum chamber of the ACS cavity. We confirmed that the NEG pump can be appropriately activated by using a small pumping station and that purging with noble gases reduces the saturation of the NEG surface. In the evacuation test of the prototype ACS cavity with the NEG pump, the partial pressure of H2 and the total pressure were reduced from 4.8 × 10-7 and 6.8 × 10-7 Pa to 2.5 × 10-7 and 4.5 × 10-7 Pa, respectively. The additional NEG pump will be installed in the ACS cavity in the fall of 2014, after which any decrease in pressure and NEG-pump lifetime will be confirmed by long-term-operation experiments.

  7. Coupling the NASA-CASA ecosystem model with a hydrologic routing algorithm for improved water management in Yosemite National Park

    NASA Astrophysics Data System (ADS)

    Teaby, A.; Johnson, E. R.; Griffin, M.; Carrillo, C.; Kannan, T.; Shupe, J. W.; Schmidt, C.

    2013-12-01

    Historic trends reveal extreme precipitation variability within the Yosemite National Park (YNP) geographic region. While California obtains greater than half of its annual water supply from the Sierra Nevada, snowpack, precipitation, and runoff can fluctuate between less than 50% and greater than 200% of climatological averages. Advances in hydrological modeling are crucial to improving water-use efficiency at the local, state, and national levels. The NASA Carnegie Ames Stanford Approach (CASA) is a global simulation model that combines multi-year satellite, climate, and other land surface databases to estimate biosphere-atmosphere exchange of energy, water, and trace gases from plants and soils. By coupling CASA with a Hydrological Routing Algorithm known as HYDRA, it is possible to calculate current water availability and observe hydrological trends within YNP. Satellite-derived inputs such as surface evapotranspiration, temperature, precipitation, land cover, and elevation were included to create a valuable decision support tool for YNP's water resource managers. These results will be of enhanced importance given current efforts to restore 81 miles of the Merced River within the park's boundary. Validations of model results were conducted using in situ stream gage measurements. The model accurately simulated observed streamflow values, achieving a relatively strong Nash-Sutcliffe model efficiency coefficient. This geospatial assessment provides a standardized method which may be repeated in both national and international water-stressed regions.

  8. Performance improvement by metal-dielectric HR coating in laterally coupled DFB laser with metal surface gratings

    NASA Astrophysics Data System (ADS)

    Jang, S. J.; Yeo, C. I.; Yu, J. S.; Lee, Y. T.

    2010-09-01

    We report the device characteristics of the metal-dielectric high-reflectivity (HR) coated 1.55 μm laterally coupled distributed feedback (DFB) laser with metal surface gratings by using holographic lithography. The HR coating films are composed of Au/Ti/SiO2. It provides a variety of advantages compared to the uncoated DFB laser on the same processed wafer while there is no degradation on current-voltage characteristics. For 3 μm wide and 300 μm long HR coated DFB laser, it exhibits a maximum output power of ˜17 mW and a threshold current of 14.2 mA at 20°C under continuous-wave mode. It is clear that the threshold current and slope efficiency are improved by 36% and 96%, respectively, due to the reduction of mirror loss. The metal-dielectric HR coating on one facet of DFB laser is found to have significantly increased characteristic temperature (i.e., T 0˜88 K). Furthermore, the stable single-mode operation with an increased single-mode suppression ratio was achieved.

  9. Improving carbohydrate production of Chlorella sorokiniana NIES-2168 through semi-continuous process coupled with mixotrophic cultivation.

    PubMed

    Wang, Yue; Chiu, Sheng-Yi; Ho, Shih-Hsin; Liu, Zhuo; Hasunuma, Tomohisa; Chang, Ting-Ting; Chang, Kuan-Fu; Chang, Jo-Shu; Ren, Nan-Qi; Kondo, Akihiko

    2016-08-01

    Biofuels from microalgae is now a hot issue of great potential. However, achieving high starch productivity with photoautotrophic microalgae is still challenging. A feasible approach to enhance the growth and target product of microalgae is to conduct mixotrophic cultivation. The appropriate acetate addition combined with CO2 supply as dual carbon sources (i.e., mixotrophic cultivation) could enhance the cell growth of some microalgae species, but the effect of acetate-mediated mixotrophic culture mode on carbohydrate accumulation in microalgae remains unclear. Moreover, there is still lack of the information concerning how to increase the productivity of carbohydrates from microalgae under acetate-amended mixotrophic cultivation and how to optimize the engineering strategies to achieve the goal. This study was undertaken to develop an optimal acetate-contained mixotrophic cultivation system coupled with effective operation strategies to markedly improve the carbohydrate productivity of Chlorella sorokiniana NIES-2168. The optimal carbohydrate productivity of 695 mg/L/d was obtained, which is the highest value ever reported. The monosaccharide in the accumulated carbohydrates is mainly glucose (i.e., 85-90%), which is very suitable for bio-alcohols fermentation. Hence, by applying the optimal process developed in this study, C. sorokiniana NIES-2168 has a high potential to serve as a feedstock for subsequent biofuels conversion. PMID:27312599

  10. Winds, Mountains, and Wildland Fire: Improved Understanding of Coupled Atmosphere-Topography-Fire Interactions Through Large-Eddy Simulation

    NASA Astrophysics Data System (ADS)

    Munoz-Esparza, D.; Sauer, J.; Linn, R.

    2015-12-01

    Anomalous and unexpected fire behavior in complex terrain continues to result in substantial loss of property and extremely dangerous conditions for firefighting field personnel. We briefly discuss proposed hypotheses of fire interactions with atmospheric flows over complex terrain that can lead to poorly-understood and potentially catastrophic scenarios. Then, our recent results of numerical investigations via large-eddy simulation of coupled atmosphere-topography-fire phenomenology with the Los Alamos National Laboratory, HiGrad-Firetec model are presented as an example of the potential for increased understanding of these complex processes. This investigation focuses on the influence of downslope surface wind enhancement through stably stratified flow over an isolated hill, and the resulting dramatic changes in fire behavior including spread rate, and intensity. Implications with respect to counter-intuitive fire behavior and extreme fire events are discussed. This work demonstrates a tremendous opportunity to immediately create safer and more effective policy for field personnel through improved predictability of atmospheric conditions over complex terrain

  11. Speed, pacing strategy and aerodynamic drafting in Thoroughbred horse racing.

    PubMed

    Spence, Andrew J; Thurman, Andrew S; Maher, Michael J; Wilson, Alan M

    2012-08-23

    Choice of pacing strategy and the benefit of aerodynamic drafting are thought to be key determinants of racing performance. These effects have largely been analysed without reference to final outcome, in small datasets with low temporal resolution, and a focus on human swimming, cycling and running. Here, we determined the position and speed of 44,803 racehorses, once per second, in 3,357 races ranging in length from 1006 to 4225 m (50.9-292.9 seconds duration) using a validated radio tracking system. We find that aerodynamic drafting has a marked effect on horse performance, and hence racing outcome. Furthermore, we demonstrate that race length-dependent pacing strategies are correlated with the fastest racing times, with some horses reaching a maximum speed in excess of 19 m s(-1). The higher speeds seen with certain pacing strategies may arise due to the nature of pack racing itself, or may be a reflection of individual capabilities, that is, corresponding to horses that perform well in roles suited to their 'front-running' or 'chaser' personality traits. PMID:22399784

  12. Determination of myocardial energetic output for cardiac rhythm pacing.

    PubMed

    Herman, Dalibor; Prevorovská, Svetlana; Marsík, Frantisek

    2007-12-01

    This research is aimed to the determination of the changes in the cardiac energetic output for three different modes of cardiac rhythm pacing. The clinical investigation of thirteen patients with the permanent dual-chamber pacemaker implantation was carried out. The patients were taken to echocardiography examination conducted by way of three pacing modes (AAI, VVI and DDD). The myocardial energetic parameters-the stroke work index (SWI) and the myocardial oxygen consumption (MVO2) are not directly measurable, however, their values can be determined using the numerical model of the human cardiovascular system. The 24-segment hemodynamical model (pulsating type) of the human cardiovascular system was used for the numerical simulation of the changes of myocardial workload for cardiac rhythm pacing. The model was fitted by well-measurable parameters for each patient. The calculated parameters were compared using the two-tailed Student's test. The differences of SWI and MVO2 between the modes AAI and VVI and the modes DDD and VVI are statistically significant (P<0.05). On the other hand, the hemodynamic effects for the stimulation modes DDD and AAI are almost identical, i.e. the differences are statistically insignificant (P>0.05). PMID:18080208

  13. Temporary epicardial pacing after cardiac surgery: a practical review. Part 2: Selection of epicardial pacing modes and troubleshooting.

    PubMed

    Reade, M C

    2007-04-01

    The first part of this two-part review discussed the indications for various types of epicardial pacing systems and an overview of the routine care of a pacemaker-dependent patient. Dual chamber temporary pulse generators now feature many of the refinements developed initially for use in permanent pacemakers. Few of these are utilised in the immediate postoperative period, often solely due to lack of familiarity with all but basic functions. The second part of the review deals with the selection of pacing modes. Troubleshooting real and apparent pacemaker malfunctions, including manual adjustment of parameters such as the AV interval, post atrial refractory period and upper rate limit, to avoid over- and undersensing, cross-talk and pacemaker-mediated tachycardia will also be addressed. PMID:17381573

  14. Dual chamber pacing mode in an atrial antitachycardia pacing device without a ventricular lead – A necessary evil

    PubMed Central

    Noheria, Amit; Friedman, Paul A.; Asirvatham, Samuel J.; McLeod, Christopher J.

    2015-01-01

    We present a case of a single chamber atrial pacemaker implanted for sinus node dysfunction and treatment of macroreentrant atrial tachycardias with atrial antitachycardia pacing. The patient presented with sustained atrial tachycardia above the detection rate, however, the device was unable to detect the tachycardia and did not deliver the programmed therapy. We discuss the nuances of the atrial tachyarrhythmia detection algorithms, and the programming strategies to maximize detection of atrial arrhythmias in a single chamber atrial pacemaker. PMID:26937101

  15. Improving Electron Transport Simulation in Mesoscopic Systems by Coupling a Classical Monte Carlo Algorithm to a Wigner Function Solver

    NASA Astrophysics Data System (ADS)

    García-García, J.; Martín, F.; Oriols, X.; Suñé, J.

    increase the simulation domains without paying a penalty in efficiency. We have modeled this coupling by using the Monte Carlo distribution of carriers in k-space in the cells adjacent to the QW as boundary conditions for the step-by-step solution of the Liouville equation, while the Wigner distribution function at the edges of the QW dictates carrier injection to the classical regions. By introducing in our tool a Poisson solver, necessary for self-consistency, we have simulated the I-V characteristic of RTD's with typical physical parameters. Realistic simulation boxes of 300nm have been considered. These are much higher than those of previous works, while the times required to achieve convergence are similar. The main qualitative features of actual devices are reproduced by means of our tool, i.e., oscillatory behavior and current plateau in the negative differential resistance region. By analyzing the potential profile and electron density distribution at various applied bias it is seen that charge accumulation in the well is maximum at resonance and no spurious or discontinuities have been found at the boundaries of the QW, which reveals that the coupling model is well-behaved. We are currently comparing the simulation results to experimental data provided by other authors. Our preliminary results seem to indicate that allowing physical parameters to slightly vary from nominal values (parameter dispersion is unavoidable at the length scales we are dealing with), a reasonable fit between simulated and experimental results is possible. The main conclusion of the work is that within the framework of the Wigner distribution function, we have developed a tool that provides improvement over previous simulators since realistic device dimensions can be considered without efficiency degradation. This allows to obtain more accurate simulated results and make the tool a potential candidate to aid in RTD device design and fabrication. This work has been supported by the Direcci

  16. Biventricular stimulation to prevent cardiac desynchronization: rationale, design, and endpoints of the 'Biventricular Pacing for Atrioventricular Block to Prevent Cardiac Desynchronization (BioPace)' study.

    PubMed

    Funck, Reinhard C; Blanc, Jean-Jacques; Mueller, Hans-Helge; Schade-Brittinger, Carmen; Bailleul, Christophe; Maisch, Bernhard

    2006-08-01

    Despite the deleterious effects of cardiac dyssynchrony and the positive effects of cardiac resynchronization therapy, patients with high-degree atrioventricular block continue to receive desynchronizing right ventricular (RV) pacing systems. Although it is unclear whether the negative effects of RV pacing and left bundle branch block (LBBB) are comparable, and whether they depend on the presence and the degree of structural heart disease, one may hypothesize that RV pacing may have similar effects to LBBB. In the BioPace trial, the long-term effects of RV pacing vs. biventricular pacing will be prospectively compared in 1200 pacemaker patients with high likelihood of mostly paced ventricular events, regardless of whether in sinus rhythm or in atrial fibrillation (AF). After echocardiographic examination of left ventricular (LV) function, patients will be randomly assigned to the implantation of an RV vs. a biventricular pacing system and followed for up to 5 years. Primary study endpoints are survival, quality of life (QoL), and the distance covered in a 6-min hall walk (6-MHW) at 24 months after implantation. Secondary endpoints are QoL and the 6-MHW result at 12 months after implantation, hospitalization rate, LV dimensions, LV ejection fraction, and the development of chronic AF and other adverse events. PMID:16864616

  17. Ecuador steps up pace of oil development activity

    SciTech Connect

    Not Available

    1992-03-23

    This paper reports that oil companies operating in Ecuador plan to quicken the pace of oil development this year. After delays in 1991, companies plan a series of projects to develop reserves discovered the past 3 years estimated at more than 600 million bbl. Oil and Gas Journal estimated Ecuador's proved crude reserves at 1.55 billion bbl as of Jan. 1, 1992. The development push is part of a larger effort needed to ensure Ecuador's status as an oil exporter into the next century. Ecuador is the smallest crude oil producer and exporter in the Organization of Petroleum Exporting Countries.

  18. Controllable Snail-Paced Light in Biological Bacteriorhodopsin Thin Film

    NASA Astrophysics Data System (ADS)

    Wu, Pengfei; Rao, D. V. G. L. N.

    2005-12-01

    We observe that the group velocity of light is reduced to an extremely low value of 0.091mm/s in a biological thin film of bacteriorhodopsin at room temperature. By exploiting unique features of a flexible photoisomerization process for coherent population oscillation, the velocity is all-optically controlled over an enormous span, from snail-paced to normal light speed, with no need of modifying the characteristics of the incident pulse. Because of the large quantum yield for the photoreaction in this biochemical system, the ultraslow light is observed even at low light levels of microwatts, indicating high energy efficiency.

  19. Paced Auditory Serial Addition Test: adult norms and moderator variables.

    PubMed

    Wiens, A N; Fuller, K H; Crossen, J R

    1997-08-01

    This study examined the performance of a sample of 821 healthy job applicants on the Paced Auditory Serial Addition Test (PASAT). Subjects had previously passed basic academic skills tests and physical examinations and were deemed free of cognitive impairment and medical illness. They were also motivated to perform well on cognitive tests. Gender, ethnicity, and education were not significant moderator variables in our subjects. Age and IQ did significantly affect PASAT test results. Normative data are stratified by age and WAIS-R Full Scale IQ scores to be useful to those who administer the PASAT in clinical practice. PMID:9342683

  20. What Controls the Pacing of 100-ky Glacial Cycles?

    NASA Astrophysics Data System (ADS)

    Raymo, M. E.; Kawamura, K.; Lisiecki, L.; Thompson, W. G.; Severinghaus, J. P.

    2006-12-01

    Climate variations over the last ~700,000 years are characterized by orbital periodicities of 100, 41 and 23 ky. While 23- and 41-ky components are understood as linear climatic responses to forcing by precession (modulated by eccentricity) and obliquity, respectively, the 100-ky cycle cannot be explained as a linear response to eccentricity. Rather, it has been suggested that the 100-ky cycle is caused by skipping of higher frequency beats which results in the bundling of either 4 or 5 precession cycles (Raymo, Paleoceanography, 1997), or 2 or 3 obliquity cycles (Huybers and Wunsch, Nature, 2005), each grouping resulting in an average 100 ky periodicity. However, verification of these competing hypotheses has not been possible because of the lack of accurately dated climate proxies. Here, using statistical tests of newly established chronologies of Antarctic climate (Kawamura et al., AGU 2006 fall meeting) and sea level high stands (Thompson, in preparation), we show that precession pacing is statistically more significant than obliquity pacing for the last five glacial terminations. We used the timings of Antarctic warmings at terminations from the Dome Fuji ice core for termination I to III, and from the Vostok core for termination IV. The timing of termination V was estimated by shifting the Dome C (EDC2) timescale to match the timing of peak MIS 11.3 with the Vostok record. The time of onset for the sea level high stands of the last four interglacial periods were estimated by correcting radiometric fossil coral ages with open-system age equations (Thompson et al., 2003, EPSL). Our results show that the null hypothesis for precession pacing can be rejected at the 3% significance level for the last five terminations from ice cores and for four terminations from sea level high stands, whereas the null hypothesis for obliquity pacing can be rejected only at >10% significance level. The statistical power of test for obliquity is high (>95% at the 10% significance

  1. Intracytoplasmic morphologically selected sperm injection results in improved clinical outcomes in couples with previous ICSI failures or male factor infertility: a meta-analysis.

    PubMed

    Setti, Amanda S; Braga, Daniela P A F; Figueira, Rita C S; Iaconelli, Assumpto; Borges, Edson

    2014-12-01

    The objective of this study was to perform the first meta-analysis to compare conventional intracytoplasmic sperm injection (ICSI) outcomes and intracytoplasmic morphologically selected sperm injection (IMSI) outcomes in couples with previous ICSI failures (IF) or male factor infertility (MF). A systematic review was performed by searching Medline database to identify articles reporting on the comparison between ICSI and IMSI outcomes in couples with IF or MF. The main outcome measures were the implantation, pregnancy and miscarriage rates. Thirteen studies fulfilled our predetermined criteria. The overall results of meta-analysis for implantation (OR: 2.88; CI: 2.13-3.89), pregnancy (OR: 2.07; CI: 1.22-3.50) and miscarriage rates (OR: 0.31; CI: 0.14-0.67) were in favor of IMSI in couples with IF. Additionally, the overall result of meta-analysis for implantation (OR: 1.56; CI: 1.11-2.18) and pregnancy rate (OR: 1.61; CI: 1.17-2.23) were in favor of IMSI in couples with MF. IMSI increases the odds of implantation by 50% and pregnancy by 60% in couples with MF. In light of improved clinical outcomes, we recommend promoting the IMSI method in couples with MF. Moreover, IMSI results in a 3-fold increase in implantation rate, a 2-fold increase in pregnancy rate and a 70% decrease in miscarriage rate as compared to ICSI in couples with IF, however, as no randomized evidence exists, randomized studies are needed to confirm the IMSI benefits in couples with IF. PMID:25461360

  2. Higher sympathetic nerve activity during ventricular (VVI) than during dual-chamber (DDD) pacing

    NASA Technical Reports Server (NTRS)

    Taylor, J. A.; Morillo, C. A.; Eckberg, D. L.; Ellenbogen, K. A.

    1996-01-01

    OBJECTIVES: We determined the short-term effects of single-chamber ventricular pacing and dual-chamber atrioventricular (AV) pacing on directly measured sympathetic nerve activity. BACKGROUND: Dual-chamber AV cardiac pacing results in greater cardiac output and lower systemic vascular resistance than does single-chamber ventricular pacing. However, it is unclear whether these hemodynamic advantages result in less sympathetic nervous system outflow. METHODS: In 13 patients with a dual-chamber pacemaker, we recorded the electrocardiogram, noninvasive arterial pressure (Finapres), respiration and muscle sympathetic nerve activity (microneurography) during 3 min of underlying basal heart rate and 3 min of ventricular and AV pacing at rates of 60 and 100 beats/min. RESULTS: Arterial pressure was lowest and muscle sympathetic nerve activity was highest at the underlying basal heart rate. Arterial pressure increased with cardiac pacing and was greater with AV than with ventricular pacing (change in mean blood pressure +/- SE: 10 +/- 3 vs. 2 +/- 2 mm Hg at 60 beats/min; 21 +/- 5 vs. 14 +/- 2 mm Hg at 100 beats/min; p < 0.05). Sympathetic nerve activity decreased with cardiac pacing and the decline was greater with AV than with ventricular pacing (60 beats/min -40 +/- 11% vs. -17 +/- 7%; 100 beats/min -60 +/- 9% vs. -48 +/- 10%; p < 0.05). Although most patients showed a strong inverse relation between arterial pressure and muscle sympathetic nerve activity, three patients with severe left ventricular dysfunction (ejection fraction < or = 30%) showed no relation between arterial pressure and sympathetic activity. CONCLUSIONS: Short-term AV pacing results in lower sympathetic nerve activity and higher arterial pressure than does ventricular pacing, indicating that cardiac pacing mode may influence sympathetic outflow simply through arterial baroreflex mechanisms. We speculate that the greater incidence of adverse outcomes in patients treated with single-chamber ventricular

  3. Improved performance of a shielded torch using ethanol in inductively coupled plasma-sector field mass spectrometry

    NASA Astrophysics Data System (ADS)

    Chen, Tao; Hu, Zhaochu; Liu, Shenghua; Liu, Yongsheng; Gao, Shan; Li, Ming; Zong, Keqing; Chen, Haihong; Hu, Shenghong

    2015-04-01

    To improve the accuracy and precision of trace element analysis, higher analytical sensitivity and lower interference are required. In this study, we investigated the effects of the addition of ethanol in combination with a shielded torch on the signal intensities of elements from 7Li to 238U, oxide yields, doubly charged ion yields, isobaric interferences and ion distributions in inductively coupled plasma-sector field mass spectrometry (ICP-SFMS). For the 39 investigated elements in this study, using the shielded torch increases the sensitivity by a factor of 17-58. The well-known drawback of using a shielded torch is that it will increase the oxide yield. In this study, the CeO+/Ce+ ratio is increased by a factor of 3.3 in the GE-on mode compared to that in the GE-off mode at normal conditions (without ethanol). In the GE-on mode, the addition of 4% ethanol in ICP-SFMS is found not only to decrease the CeO+/Ce+ ratio by a factor of 4 but also to suppress the Ce2 +/Ce+ ratio by a factor of 4.2. In large contrast, the effect of 2-6% ethanol on the oxide yield and doubly charged ratio is minimal in the GE-off mode. Except for As, Se, Sb, Te and Au, for which the signal intensities are increased by a factor of 1.4-3.7 in the presence of 2-6% ethanol, an increased concentration of ethanol suppresses intensities of other elements. In the GE-off mode, the suppression of the analyte signal due to increased ethanol concentration is more significant than that in the GE-on mode. Compared to the spatial profiles of the ion distributions in the normal mode (without ethanol), the addition of 2-4% ethanol leads to significantly wider axial and radial profiles. The significantly wider axial and radial ion distribution had a dilution effect on the ion densities, which subsequently reduced the ion signal intensities. The addition of 4% ethanol was also found to suppress the interferences of Xe by a factor of 2.8 and increase the sensitivity of Te determination in ICP-SFMS by a

  4. Paced QRS duration and myocardial scar amount: predictors of long-term outcome of right ventricular apical pacing.

    PubMed

    Lee, Seung-Ah; Cha, Myung-Jin; Cho, Youngjin; Oh, Il-Young; Choi, Eue-Keun; Oh, Seil

    2016-07-01

    Long-term right ventricular apical pacing (RVAP) is reportedly associated with heart failure (HF) development. However, the predictors of pacing-induced HF (PHF) remained unclear. We retrospectively enrolled 234 patients without structural heart disease who underwent a permanent pacemaker implantation with RVAP between 1982 and 2004. RVAP-induced HF was defined as left ventricular ejection fraction decrease >5 % with HF symptom without other HF development etiology. The QRS duration of a paced beat (pQRSd) and myocardial scar score were analyzed from each patient's 12-lead ECG. During a mean 15.6 years (range 3.3-30.0 years), 48 patients (20.5 %) patients developed RVAP-induced HF. The PHF group patients had a longer pQRSd (192.4 ± 13.5 vs. 175.7 ± 14.7 ms in non-PHF patients, p < 0.001) and a higher myocardial scar score (5.2 ± 1.9 vs. 2.7 ± 1.9, respectively p < 0.001). In multivariate Cox regression analysis, old age at implantation [Hazard ratio (HR) 1.62, 95 % confidential interval (CI) 1.22-2.16, p = 0.001], a longer pQRSd (HR 1.54, 95 % CI 1.15-2.05, p = 0.003), a higher myocardial scar score (HR 1.23, 95 % CI 1.03-1.49, p = 0.037), and a higher percentage of ventricular pacing (HR 1.31, 95 % CI 1.01-1.49, p = 0.010) were independent predictors of PHF. Based on the results of the receiver-operating characteristic (ROC) curve, the pQRSd cutoff was 185 ms (AUC 0.79, sensitivity 66.7 %, specificity 76.3 %) and myocardial scar score cutoff value was 4 (AUC 0.81, sensitivity 81.3 %, specificity 66.1 %). The pQRSd was positively correlated with scar score (r = 0.70, p < 0.001). pQRSd ≥185 ms and/or myocardial scar score ≥4 might be independent long-term prognostic markers of PHF. PMID:26142378

  5. The pace of East African monsoon evolution during the Holocene

    NASA Astrophysics Data System (ADS)

    Weldeab, Syee; Menke, Valerie; Schmiedl, Gerhard

    2014-03-01

    African monsoon precipitation experienced a dramatic change in the course of the Holocene. The pace with which the African monsoon shifted from a strong early to middle to a weak late Holocene is critical for our understanding of climate dynamics, hydroclimate-vegetation interaction, and shifts of prehistoric human settlements, yet it is controversially debated. On the basis of planktonic foraminiferal Ba/Ca time series from the eastern Mediterranean Sea, here we present a proxy record of Nile River runoff that provides a spatially integrated measure of changes in East African monsoon (EAM) precipitation. The runoff record indicates a markedly gradual middle to late Holocene EAM transition that lasted over 3500 years. The timing and pace of runoff change parallels those of insolation and vegetation changes over the Nile basin, indicating orbitally forced variation of insolation as the main EAM forcing and the absence of a nonlinear precipitation-vegetation feedback. A tight correspondence between a threshold level of Nile River runoff and the timing of occupation/abandonment of settlements suggests that along with climate changes in the eastern Sahara, the level of Nile River and intensity of summer floods were likely critical for the habitability of the Nile Valley (Egypt).

  6. Effects of spironolactone towards rabbit atrial remodeling with rapid pacing.

    PubMed

    Wang, Lian-Fa; Gu, Lei; Huang, Meng-Xun; Zhou, Wen-Bing; Li, Hua; Zhang, Bang-Zhu

    2016-01-01

    This study aimed to observe the effects of spironolactone towards the rabbit atrial remodeling with rapid atrial pacing (RAP). 30 rabbits were randomly divided into control group, RAP group and spironolactone group, with 10 rabbits in each group. RAP was performed at the speed of 800 beats/min for 8 h, atrial effective refractory period (AERP) was determined before and at the 1(st), 2(nd), 4(th), 6(th) and 8(th) of the pacing, the expressions of atrial muscular calcium channel α1C subunit and β1 subunit mRNA were performed the RT-PCR detection, and ultrastructural changes of atrial myocytes were observed. AERP of RAP group shortened, with poor frequency adaptability; the expressions of calcium channel α1C subunit and β1 subunit mRNA decreased 22% and 26%, respectively, when compared with the control group; ultrastructure of atrial myocytes changed significantly. AERP of spironotlactone group shortened less that RAP group, and the frequency adaptability was maintained, the decreased expressions of calcium channel α1C subunit and β1 subunit mRNA significantly reduced. RAP could cause atrial remodeling, while spironolactone could inhibit RAP-induced atrial remodeling. PMID:26826809

  7. The Mixed-Phase Arctic Cloud Experiment (M-PACE)

    NASA Technical Reports Server (NTRS)

    Verlinde, J.; Harrington, J. Y.; McFarquhar, G. M.; Yannuzzi, V. T.; Avramov, A.; Greenberg, S.; Johnson, N.; Zhang, G.; Poellot, M. R.; Mather, J. H.; Turner, D. D.; Eloranta, E. W.; Zak, B. D.; Prenni, A. J.; Daniel, J. S.; Kok, G. L.; Tobin, D. C.; Holz, R.; Sassen, K.; Spangenberg, D.; Minnis, P.; Tooman, T. P.; Ivey, M. D.; Richardson, S. J.; Bahramann, C. P.

    2007-01-01

    The Mixed-Phase Arctic Cloud Experiment (M-PACE) was conducted September 27 through October 22, 2004 on the North Slope of Alaska. The primary objective was to collect a data set suitable to study interactions between microphysics, dynamics and radiative transfer in mixed-phase Arctic clouds. Observations taken during the 1997/1998 Surface Heat and Energy Budget of the Arctic (SHEBA) experiment revealed that Arctic clouds frequently consist of one (or more) liquid layers precipitating ice. M-PACE sought to investigate the physical processes of these clouds utilizing two aircraft (an in situ aircraft to characterize the microphysical properties of the clouds and a remote sensing aircraft to constraint the upwelling radiation) over the Department of Energy s Atmospheric Radiation Measurement (ARM) Climate Research Facility (ACRF) on the North Slope of Alaska. The measurements successfully documented the microphysical structure of Arctic mixed-phase clouds, with multiple in situ profiles collected in both single-layer and multi-layer clouds over two ground-based remote sensing sites. Liquid was found in clouds with temperatures down to -30 C, the coldest cloud top temperature below -40 C sampled by the aircraft. Remote sensing instruments suggest that ice was present in low concentrations, mostly concentrated in precipitation shafts, although there are indications of light ice precipitation present below the optically thick single-layer clouds. The prevalence of liquid down to these low temperatures could potentially be explained by the relatively low measured ice nuclei concentrations.

  8. Data reproducibility of pace strategy in a laboratory test run

    PubMed Central

    de França, Elias; Xavier, Ana Paula; Hirota, Vinicius Barroso; Côrrea, Sônia Cavalcanti; Caperuto, Érico Chagas

    2016-01-01

    This data paper contains data related to a reproducibility test for running pacing strategy in an intermittent running test until exhaustion. Ten participants underwent a crossover study (test and retest) with an intermittent running test. The test was composed of three-minute sets (at 1 km/h above Onset Blood Lactate Accumulation) until volitional exhaustion. To assess pace strategy change, in the first test participants chose the rest time interval (RTI) between sets (ranging from 30 to 60 s) and in the second test the maximum RTI values were either the RTI chosen in the first test (maximum RTI value), or less if desired. To verify the reproducibility of the test, rating perceived exertion (RPE), heart rate (HR) and blood plasma lactate concentration ([La]p) were collected at rest, immediately after each set and at the end of the tests. As results, RTI, RPE, HR, [La]p and time to exhaustion were not statistically different (p>0.05) between test and retest, as well as they demonstrated good intraclass correlation. PMID:27081672

  9. The Transfer Functions of Cardiac Tissue during Stochastic Pacing

    PubMed Central

    de Lange, Enno; Kucera, Jan P.

    2009-01-01

    Abstract The restitution properties of cardiac action potential duration (APD) and conduction velocity (CV) are important factors in arrhythmogenesis. They determine alternans, wavebreak, and the patterns of reentrant arrhythmias. We developed a novel approach to characterize restitution using transfer functions. Transfer functions relate an input and an output quantity in terms of gain and phase shift in the complex frequency domain. We derived an analytical expression for the transfer function of interbeat intervals (IBIs) during conduction from one site (input) to another site downstream (output). Transfer functions can be efficiently obtained using a stochastic pacing protocol. Using simulations of conduction and extracellular mapping of strands of neonatal rat ventricular myocytes, we show that transfer functions permit the quantification of APD and CV restitution slopes when it is difficult to measure APD directly. We find that the normally positive CV restitution slope attenuates IBI variations. In contrast, a negative CV restitution slope (induced by decreasing extracellular [K+]) amplifies IBI variations with a maximum at the frequency of alternans. Hence, it potentiates alternans and renders conduction unstable, even in the absence of APD restitution. Thus, stochastic pacing and transfer function analysis represent a powerful strategy to evaluate restitution and the stability of conduction. PMID:19134481

  10. Data reproducibility of pace strategy in a laboratory test run.

    PubMed

    de França, Elias; Xavier, Ana Paula; Hirota, Vinicius Barroso; Côrrea, Sônia Cavalcanti; Caperuto, Érico Chagas

    2016-06-01

    This data paper contains data related to a reproducibility test for running pacing strategy in an intermittent running test until exhaustion. Ten participants underwent a crossover study (test and retest) with an intermittent running test. The test was composed of three-minute sets (at 1 km/h above Onset Blood Lactate Accumulation) until volitional exhaustion. To assess pace strategy change, in the first test participants chose the rest time interval (RTI) between sets (ranging from 30 to 60 s) and in the second test the maximum RTI values were either the RTI chosen in the first test (maximum RTI value), or less if desired. To verify the reproducibility of the test, rating perceived exertion (RPE), heart rate (HR) and blood plasma lactate concentration ([La]p) were collected at rest, immediately after each set and at the end of the tests. As results, RTI, RPE, HR, [La]p and time to exhaustion were not statistically different (p>0.05) between test and retest, as well as they demonstrated good intraclass correlation. PMID:27081672

  11. Pacing a data transfer operation between compute nodes on a parallel computer

    DOEpatents

    Blocksome, Michael A.

    2011-09-13

    Methods, systems, and products are disclosed for pacing a data transfer between compute nodes on a parallel computer that include: transferring, by an origin compute node, a chunk of an application message to a target compute node; sending, by the origin compute node, a pacing request to a target direct memory access (`DMA`) engine on the target compute node using a remote get DMA operation; determining, by the origin compute node, whether a pacing response to the pacing request has been received from the target DMA engine; and transferring, by the origin compute node, a next chunk of the application message if the pacing response to the pacing request has been received from the target DMA engine.

  12. PACES Participation in Educational Outreach Programs at the University of Texas at El Paso

    NASA Technical Reports Server (NTRS)

    Dodge, Rebecca L.

    1997-01-01

    The University of Texas at El Paso (UTEP) is involved in several initiatives to improve science education within the El Paso area public schools. These include outreach efforts into the K- 12 classrooms; training programs for in-service teachers; and the introduction of a strong science core curricula within the College of Education. The Pan American Center for Earth and Environmental Studies (PACES), a NASA-funded University Research Center, will leverage off the goals of these existing initiatives to provide curriculum support materials at all levels. We will use currently available Mission to Planet Earth (MTPE) materials as well as new materials developed specifically for this region, in an effort to introduce the Earth System Science perspective into these programs. In addition, we are developing curriculum support materials and classes within the Geology and Computer Departments, to provide education in the area of remote sensing and GIS applications at the undergraduate and graduate levels.

  13. Two unsung heroes of closed-chest cardiac pacing: Green and McWilliam.

    PubMed

    Geddes, L A

    1994-07-01

    In the latter half of the last century, cardiorespiratory arrest was not uncommon due to the anesthetic used (chloroform). Animal studies showed that the heart could be paced. One physician (Green) resuscitated 5 of 7 cardiac arrest patients with single stimuli applied to body surface electrodes. Another (McWilliam) issued a proposal for adoption of closed-chest pacing and provided information on the procedure. The following historical footnote describes these pioneering events in the history of cardiac pacing. PMID:7937239

  14. Improving the Out-Coupling of a Metal-Metal Terahertz Frequency Quantum Cascade Laser Through Integration of a Hybrid Mode Section into the Waveguide

    NASA Astrophysics Data System (ADS)

    Fobbe, Tobias; Nong, Hanond; Schott, Rüdiger; Pal, Shovon; Markmann, Sergej; Hekmat, Negar; Zhu, Jingxuan; Han, Yingjun; Li, Lianhe; Dean, Paul; Linfield, Edmund H.; Davies, A. Giles; Wieck, Andreas D.; Jukam, Nathan

    2016-05-01

    A hybrid mode section is integrated into the end of the metal-metal waveguide of a terahertz (THz) frequency quantum cascade laser (QCL) by removing sub-wavelength portions of the top metal layer. This allows a hybrid mode to penetrate into the air, which reduces the effective index of the mode and improves the out-coupling performance at the facet. The transmission of the hybrid section is further increased by ensuring its length fulfills the criterion for constructive interference. These simple modifications to a 2.5-THz metal-metal QCL waveguide result in a significant increase in the output emission power. In addition, simulations show that further improvements in out-coupling efficiency can be achieved for lower frequencies with effective refractive indices close to the geometric mean of the indices of the metal-metal waveguide and air.

  15. Spatial discordance and phase reversals during alternate pacing in discrete-time kinematic and cardiomyocyte ionic models

    NASA Astrophysics Data System (ADS)

    Weinberg, Seth H.

    2015-10-01

    Alternans, a beat-to-beat alternation in the cardiac action potential duration (APD), is a dynamical instability linked with the initiation of arrhythmias and sudden cardiac death, and arises via a period-doubling bifurcation when myocytes are stimulated at fast rates. In this study, we analyze the stability of a propagating electrical wave in a one-dimensional cardiac myocyte model in response to an arrhythmogenic rhythm known as alternate pacing. Using a discrete-time kinematic model and complex frequency (Z) domain analysis, we derive analytical expressions to predict phase reversals and spatial discordance in the interbeat interval (IBI) and APD, which, importantly, cannot be predicted with a model that neglects the influence of cell coupling on repolarization. We identify key dimensionless parameters that determine the transition from spatial concordance to discordance. Finally, we show that the theoretical predictions agree closely with numerical simulations of an ionic myocyte model, over a wide range of parameters, including variable IBI, altered ionic current gating, and reduced cell coupling. We demonstrate a novel approach to predict instability in cardiac tissue during alternate pacing and further illustrate how this approach can be generalized to more detail models of myocyte dynamics.

  16. A comparison of two stab-on unipolar epicardial pacing leads in children.

    PubMed

    Hamilton, R M; Chiu, C; Gow, R M; Williams, W G

    1997-03-01

    The Oscor MP52V and Medtronic 4951 leads have similar construction and intended application. To determine if one of these designs was more suited to pediatric pacing, we reviewed implant, 3 month, and 12 months follow-up thresholds for all 18 MP52V implants at our institution from December 1989 to April 1991 and compared them to the 4951 implants from January 1982 to October 1989. Lead survival for the MP52V implants was compared to the most recent 36 4951 implants. Patients ranged in ages from 2 days-16 years (median = 4 years) and required antibradycardia pacing for congenital or acquired heart disease. Patients were compared for weight and proportion of atrial leads in each group by t-test and Fisher exact tests respectively. Energy thresholds were assessed in microJ and compared by t-test. Lead survival was defined by abandonment or replacement for any reason. Kaplan & Meier survival curves were plotted and compared by Gehan's Wilcoxan Test. There were no significant differences between the MP52V and 4951 groups for age at implant (53 months vs 80 months) or proportion of atrial implants (5/18 vs 11/36). Lead survival was poor but did not differ significantly (70% vs 78% cumulative survival at 3 years), usually failing by exit block. Implant and follow-up thresholds did not differ significantly between leads. The MP52V did not provide significant improvement in performance over the 4951. New epicardial lead designs are needed to improve lead survival and thresholds in children. PMID:9080489

  17. Rate-related accelerating (autodecremental) atrial pacing for reversion of paroxysmal supraventricular tachycardia.

    PubMed

    Nathan, A; Hellestrand, K; Ward, D; Spurrell, R; Camm, J

    1982-01-01

    Twenty consecutive patients with paroxysmal intra A-V nodal or atrio-ventricular tachycardia had a new tachycardia reversion pacing modality evaluated during routine electrophysiological study. The pacing was controlled by a micropressor interfaced with a stimulator connected to a right atrial pacing electrode. On detection of tachycardia the first pacing cycle interval is equal to the tachycardia cycle length minus a decrement value D. Each subsequent pacing cycle is further reduced by the same value of D, thus accelerating the pacing burst until a plateau of 100 beats/min faster than tachycardia (with an absolute lower limit of 275 beats/min) is reached. Seven different values of D (2, 4, 8, 16, 24, 34, 50 msec) were assessed in combination with three different durations of pacing P (500, 5000 msec). With P:500, only 2/20 tachycardias were terminated, but with P:1000, 16/20 were terminated. With P:5000 all were terminated and the combination successful in all patients was P:5000 and D:16. No unwanted arrhythmias were induced. In contrast, competitive constant rate overdrive atrial pacing accomplished tachycardia termination in all cases, but in four instances resulted in atrial flutter or fibrillation. Autodecremental pacing, which tends to avoid stimulation in the vulnerable period, allowed safe and successful termination of all tachycardias evaluated in this study. PMID:7069321

  18. Correcting a block?: successful experience of a small British pacing centre.

    PubMed Central

    Godden, D J; MacCulloch, M S; Sandhu, P S; Kerr, F

    1987-01-01

    The establishment of a local permanent pacemaker service in a district general hospital increased the pacemaker implantation rate from 22 per million population per year to 152 per million population per year over the first 6 years of the service. Forty eight per cent of patients were referred by general practitioners and 52% by hospital specialists. Single chamber demand pacing (VVI) was used exclusively. Indications for pacing and complications were comparable to those of specialist cardiac centres. Management of symptomatic bradycardia by cardiac pacing in the United Kingdom may be facilitated by further development of small pacing centres. PMID:3676039

  19. Nuclear magnetic resonance imaging in patients with cardiac pacing devices.

    PubMed

    Buendía, Francisco; Sánchez-Gómez, Juan M; Sancho-Tello, María J; Olagüe, José; Osca, Joaquín; Cano, Oscar; Arnau, Miguel A; Igual, Begoña

    2010-06-01

    Currently, nuclear magnetic resonance imaging is contraindicated in patients with a pacemaker or implantable cardioverter-defibrillator. This study was carried out because the potential risks in this situation need to be clearly defined. This prospective study evaluated clinical and electrical parameters before and after magnetic resonance imaging was performed in 33 patients (five with implantable cardioverter-defibrillators and 28 with pacemakers). In these patients, magnetic resonance imaging was considered clinically essential. There were no clinical complications. There was a temporary communication failure in two cases, sensing errors during imaging in two cases, and a safety signal was generated in one pacemaker at the maximum magnetic resonance frequency and output level. There were no technical restrictions on imaging nor were there any permanent changes in the performance of the cardiac pacing device. PMID:20515632

  20. 1974 Arizona P.A.C.E. participation.

    PubMed

    Zabezensky, F

    1976-12-01

    Members of the Arizona State Society for Medical Technology were contacted to ascertain their knowledge of the P.A.C.E. program as well as to obtain release of the transcripts for those who participated during 1974. Observations regarding reported credits were noted. The Analysis of Variance test with Scheffe comparison was utilized to determine if any characteristic accounted for the difference in total continuing education hours reported. It was concluded that residence location, marital status, sex, age, degree level, length of membership in ASMT, years experience, employment extent, place of employment, and number of beds at place of employment had no significant effect on the total hours reported. A significant difference in total hours reported was noted for those individuals who reported either CEU or college credits. A significant difference was also noted in the total hours reported with respect to job description. PMID:998653

  1. Pacing and Defibrillators in Complex Congenital Heart Disease

    PubMed Central

    Chubb, Henry; O’Neill, Mark; Rosenthal, Eric

    2016-01-01

    Device therapy in the complex congenital heart disease (CHD) population is a challenging field. There is a myriad of devices available, but none designed specifically for the CHD patient group, and a scarcity of prospective studies to guide best practice. Baseline cardiac anatomy, prior surgical and interventional procedures, existing tachyarrhythmias and the requirement for future intervention all play a substantial role in decision making. For both pacing systems and implantable cardioverter defibrillators, numerous factors impact on the merits of system location (endovascular versus non-endovascular), lead positioning, device selection and device programming. For those with Fontan circulation and following the atrial switch procedure there are also very specific considerations regarding access and potential complications. This review discusses the published guidelines, device indications and the best available evidence for guidance of device implantation in the complex CHD population. PMID:27403295

  2. Coastal oceanography sets the pace of rocky intertidal community dynamics

    PubMed Central

    Menge, B. A.; Lubchenco, J.; Bracken, M. E. S.; Chan, F.; Foley, M. M.; Freidenburg, T. L.; Gaines, S. D.; Hudson, G.; Krenz, C.; Leslie, H.; Menge, D. N. L.; Russell, R.; Webster, M. S.

    2003-01-01

    The structure of ecological communities reflects a tension among forces that alter populations. Marine ecologists previously emphasized control by locally operating forces (predation, competition, and disturbance), but newer studies suggest that inputs from large-scale oceanographically modulated subsidies (nutrients, particulates, and propagules) can strongly influence community structure and dynamics. On New Zealand rocky shores, the magnitude of such subsidies differs profoundly between contrasting oceanographic regimes. Community structure, and particularly the pace of community dynamics, differ dramatically between intermittent upwelling regimes compared with relatively persistent down-welling regimes. We suggest that subsidy rates are a key determinant of the intensity of species interactions, and thus of structure in marine systems, and perhaps also nonmarine communities. PMID:14512513

  3. The Influence of Collective Behavior on Pacing in Endurance Competitions

    PubMed Central

    Renfree, Andrew; Crivoi do Carmo, Everton; Martin, Louise; Peters, Derek M.

    2015-01-01

    A number of theoretical models have been proposed in recent years to explain pacing strategies observed in individual competitive endurance events. These have typically related to the internal regulatory processes that inform the making of decisions relating to muscular work rate. Despite a substantial body of research which has investigated the influence of collective group dynamics on individual behaviors in various animal species, this issue has not been comprehensively studied in individual athletic events. This is somewhat surprising given that athletes often directly compete in close proximity to one another, and that collective behavior has also been observed in other human environments including pedestrian interactions and financial market trading. Whilst the reasons for adopting collective behavior are not fully understood, collective behavior is thought to result from individual agents following simple local rules that result in seemingly complex large systems that act to confer some biological advantage to the collective as a whole. Although such collective behaviors may generally be beneficial, competitive endurance events are complicated by the fact that increasing levels of physiological disruption as activity progresses may compromise the ability of some individuals to continue to interact with other group members. This could result in early fatigue and relative underperformance due to suboptimal utilization of physiological resources by some athletes. Alternatively, engagement with a collective behavior may benefit all due to a reduction in the complexity of decisions to be made and a subsequent reduction in cognitive loading and mental fatigue. This paper seeks evidence for collective behavior in previously published analyses of pacing behavior and proposes mechanisms through which it could potentially be either beneficial, or detrimental to individual performance. It concludes with suggestions for future research to enhance understanding of this

  4. Seasonal Pacing - Match Importance Affects Activity in Professional Soccer.

    PubMed

    Link, Daniel; de Lorenzo, Michael F

    2016-01-01

    This research explores the influence of match importance on player activity in professional soccer. Therefore, we used an observational approach and analyzed 1,211 matches of German Bundesliga and 2nd Bundesliga. The importance measurement employed is based on post season consequences of teams involved in a match. This means, if a match result could potentially influence the final rank, and this rank would lead to different consequences for a team, such as qualification for Champions League opposed to qualification for Europe League, then this match is classified as important; otherwise not. Activity was quantified by TOTAL DISTANCE COVERED, SPRINTS, FAST RUNS, DUELS, FOULS and ATTEMPTS. Running parameters were recorded using a semi-automatic optical tracking system, while technical variables were collected by professional data loggers. Based on our importance classification, low important matches occurred at the beginning of round 29. A two-way ANOVA indicates significantly increased FAST RUNS (+4%, d = 0.3), DUELS (+16%, d = 1.0) and FOULS (+36%, d = 1.2) in important matches compared to low important ones. For FAST RUNS and FOULS, this effect only exists in Bundesliga. A comparison of the two leagues show that TOTAL DISTANCE COVERED (+3%, d = 0.9), SPRINTS (+25%, d = 1.4) and FAST RUNS (+15%, d = 1.4) are higher compared to 2nd Bundesliga, whilst FOULS is less in Bundesliga (-7%, d = 0.3). No difference in player activity was found between matches at the beginning of a season (round 1-6) and at the end of a season (round 29-34). We conclude that match importance influences player activity in German professional soccer. The most reasonable explanation is a conscious or unconscious pacing strategy, motivated by preserving abilities or preventing injury. Since this tendency mainly exists in Bundesliga, this may suggest that more skilled players show a higher awareness for the need of pacing. PMID:27281051

  5. Seasonal Pacing - Match Importance Affects Activity in Professional Soccer

    PubMed Central

    Link, Daniel; de Lorenzo, Michael F.

    2016-01-01

    This research explores the influence of match importance on player activity in professional soccer. Therefore, we used an observational approach and analyzed 1,211 matches of German Bundesliga and 2nd Bundesliga. The importance measurement employed is based on post season consequences of teams involved in a match. This means, if a match result could potentially influence the final rank, and this rank would lead to different consequences for a team, such as qualification for Champions League opposed to qualification for Europe League, then this match is classified as important; otherwise not. Activity was quantified by TOTAL DISTANCE COVERED, SPRINTS, FAST RUNS, DUELS, FOULS and ATTEMPTS. Running parameters were recorded using a semi-automatic optical tracking system, while technical variables were collected by professional data loggers. Based on our importance classification, low important matches occurred at the beginning of round 29. A two-way ANOVA indicates significantly increased FAST RUNS (+4%, d = 0.3), DUELS (+16%, d = 1.0) and FOULS (+36%, d = 1.2) in important matches compared to low important ones. For FAST RUNS and FOULS, this effect only exists in Bundesliga. A comparison of the two leagues show that TOTAL DISTANCE COVERED (+3%, d = 0.9), SPRINTS (+25%, d = 1.4) and FAST RUNS (+15%, d = 1.4) are higher compared to 2nd Bundesliga, whilst FOULS is less in Bundesliga (-7%, d = 0.3). No difference in player activity was found between matches at the beginning of a season (round 1–6) and at the end of a season (round 29–34). We conclude that match importance influences player activity in German professional soccer. The most reasonable explanation is a conscious or unconscious pacing strategy, motivated by preserving abilities or preventing injury. Since this tendency mainly exists in Bundesliga, this may suggest that more skilled players show a higher awareness for the need of pacing. PMID:27281051

  6. Head-to-head running race simulation alters pacing strategy, performance, and mood state.

    PubMed

    Tomazini, Fabiano; Pasqua, Leonardo A; Damasceno, Mayara V; Silva-Cavalcante, Marcos D; de Oliveira, Fernando R; Lima-Silva, Adriano E; Bertuzzi, Rômulo

    2015-10-01

    The objective of this study was to analyze the influence of the presence and absence of competitors on pacing, overall running performance, and mood state during a self-paced 3-km run. Nine recreational runners participated in this study. They performed the following tests: a) an incremental test to exhaustion to measure the respiratory compensation point (RCP), maximal oxygen uptake, and peak treadmill speed; b) a submaximal speed constant test to measure running economy; and c) two 3-km running time trials performed collectively (COL, head-to-head competition) or individually (IND, performed alone) to establish pacing and running performance. The COL condition was formed of a group of four runners or five runners. Runners were grouped by matched performance times and to retain head-to-head characteristics.A mood state profile questionnaire was completed before and after the 3-km running time trial. The overall performance was better in the COL than in the IND (11.75 ± 0.05 min vs. 12.25 ± 0.06 min, respectively; p = 0.04). The running speeds during the first 500 m were significantly greater in COL (16.8 ± 2.16 km·h−1) than in IND (15.3 ± 2.45 km·h−1) (p = 0.03).The gain in running speed from IND to COL during the first 400 m (i.e. running speed in COL less running speed in IND) was significantly correlated with the RCP (r = 0.88; p = 0.05). The vigor score significantly decreased from pre- to post-running in COL (p=0.05), but not in IND (p=0.20). Additionally, the post running vigor was significantly higher in IND compared to COL (p = 0.03).These findings suggested that the presence of competitors induces a fast start, which results in an improved overall performance and reduced post-exercise vigor scores, compared to an individual run. PMID:26013576

  7. Understanding the relation between urbanization and the eco-environment in China's Yangtze River Delta using an improved EKC model and coupling analysis.

    PubMed

    Zhao, Yabo; Wang, Shaojian; Zhou, Chunshan

    2016-11-15

    Better understanding the relationship between urbanization (U) and the eco-environment (E) is necessary to coordinate the development of them. Using a comprehensive index system for U and E with statistic data, and an improved environmental Kuznets curve (EKC) model and dynamic coordination coupling degree (CCD) model, this study addressed the relationship between U and E in the Yangtze River Delta (YRD) in the period 1980-2013. The main conclusions were as follows: (1) Economic urbanization and eco-environment endowment were the highest weighted factors in the U and E system respectively, and thus constitute the key factors. (2) Differentiated inverted-U curves were shown to exist in the relation between U and E across the cities studied, thereby confirming the improved EKC hypothesis. We further found economically developed areas to have higher urbanization levels than less developed areas at the point at which the curve inflects, less developed areas have higher eco-environmental pressure at inflection. Before the appearance of the inflection point, a striking positive correlation was observed between eco-environmental pressure and the urbanization level, while a negative correlation was found to follow it. (3) A dynamic coordination coupling relation was found to exist between U and E, which conforms to an S-shaped curve. The coordination coupling process in the YRD has gradually moved from a "low-grade symbiosis" stage into a "break-in development" stage, but the pattern of coordination belonging to the eco-environment part of the relation was found to always show some lag. The dynamic CCD model showed a difference in the spatial distribution of CCD, presenting higher values in the periphery of the region, and lower values in the center during the study period. The improved EKC and coupling analysis detailed in this study may help Chinese decision makers to formulate sustainable measures to balance urbanization development and eco-environment protection. PMID

  8. Effects of personality, perceptual difficulty and pacing of a task on productivity, job satisfaction, and physiological stress.

    PubMed

    Salvendy, G; Humphreys, A P

    1979-08-01

    The relative psychological, physiological, and performance advantages and disadvantages of utilizing machine-paced and self-paced work were examined by having 12 subjects perform a marking-stapling task at 2 levels of perceptual difficulty and under 2 pacing conditions for 30 min. each. (a) 3 subjects who on the personality tests were identified as introverted, reserved, and trusting preferred to work in the machine-paced condition, while 9 subjects who were identified as extroverted, outgoing and suspicious preferred the self-paced condition, (b) the performance errors in machine-paced operation were 372% higher than for self-paced work, and (c) there were no differences between machine-paced and self-paced work on physiological variables, except for sinus arrhythmia for the task with high perceptual load, and quantity of production. PMID:503740

  9. A role for PACE4 in the proteolytic activation of anthrax toxin protective antigen.

    PubMed Central

    Gordon, V M; Rehemtulla, A; Leppla, S H

    1997-01-01

    Several bacterial protein toxins require activation by eukaryotic proteases. Previous studies have shown that anthrax toxin protective antigen (PA), Pseudomonas exotoxin A (PE), and diphtheria toxin (DT) are cleaved by furin C-terminal to the sequences RKKR, RQPR, and RVRR, respectively. Because furin-deficient cells retain some sensitivity to PA and DT, it is evident that other cellular proteases can activate these toxins. Whereas furin has been shown to require arginine residues at positions -1 and -4 for substrate recognition, another protease with an activity which could substitute for furin in toxin activation, the furin-related protease PACE4, requires basic residues in the -1, -2, and -4 positions of the substrate sequence. To examine the relative roles of furin and PACE4 in toxin activation, we used furin-deficient CHO cells (FD11 cells) transfected with either the furin (FD11/furin cells) or PACE4 (FD11/PACE4 cells) gene. Mutant PA proteins containing the cleavage sequence RAAR or KR were cytotoxic toward cells expressing only PACE4. In vitro cleavage data demonstrated that PACE4 can recognize RAAR and, to a much lesser extent, KR and RR. When extracts from PACE4-transfected cells were used as a source of proteases, PACE4 had minimal activity, indicating that it had been partially inactivated or did not remain associated with the cell membranes. Cleavage of iodinated PA containing the sequence RKKR or RAAR was detected on the surface of all cell types tested, but cleavage of a dibasic sequence was detected only intracellularly and only in cells that expressed furin or PACE4. The data provide evidence that PACE4 is present at the exterior of cells, that it plays a role in the proteolytic activation of anthrax toxin PA, and that PACE4 can activate substrates at the sequence RAAR or KR. PMID:9234799

  10. Improving wind energy forecasts using an Ensemble Kalman Filter data assimilation technique in a fully coupled hydrologic and atmospheric model

    NASA Astrophysics Data System (ADS)

    Williams, J. L.; Maxwell, R. M.; Delle Monache, L.

    2012-12-01

    Wind power is rapidly gaining prominence as a major source of renewable energy. Harnessing this promising energy source is challenging because of the chaotic nature of wind and its propensity to change speed and direction over short time scales. Accurate forecasting tools are critical to support the integration of wind energy into power grids and to maximize its impact on renewable energy portfolios. Numerous studies have shown that soil moisture distribution and land surface vegetative processes profoundly influence atmospheric boundary layer development and weather processes on local and regional scales. Using the PF.WRF model, a fully-coupled hydrologic and atmospheric model employing the ParFlow hydrologic model with the Weather Research and Forecasting model coupled via mass and energy fluxes across the land surface, we have explored the connections between the land surface and the atmosphere in terms of land surface energy flux partitioning and coupled variable fields including hydraulic conductivity, soil moisture and wind speed, and demonstrated that reductions in uncertainty in these coupled fields propagate through the hydrologic and atmospheric system. We have adapted the Data Assimilation Research Testbed (DART), an implementation of the robust Ensemble Kalman Filter data assimilation algorithm, to expand our capability to nudge forecasts produced with the PF.WRF model using observational data. Using a semi-idealized simulation domain, we examine the effects of assimilating observations of variables such as wind speed and temperature collected in the atmosphere, and land surface and subsurface observations such as soil moisture on the quality of forecast outputs. The sensitivities we find in this study will enable further studies to optimize observation collection to maximize the utility of the PF.WRF-DART forecasting system.

  11. New horizons in schizophrenia treatment: autophagy protection is coupled with behavioral improvements in a mouse model of schizophrenia

    PubMed Central

    Merenlender-Wagner, Avia; Shemer, Zeev; Touloumi, Olga; Lagoudaki, Roza; Giladi, Eliezer; Andrieux, Annie; Grigoriadis, Nikolaos C; Gozes, Illana

    2015-01-01

    Autophagy plays a key role in the pathophysiology of schizophrenia as manifested by a 40% decrease in BECN1/Beclin 1 mRNA in postmortem hippocampal tissues relative to controls. This decrease was coupled with the deregulation of the essential ADNP (activity-dependent neuroprotector homeobox), a binding partner of MAP1LC3B/LC3B (microtubule-associated protein 1 light chain 3 β) another major constituent of autophagy. The drug candidate NAP (davunetide), a peptide fragment from ADNP, enhanced the ADNP-LC3B interaction. Parallel genetic studies have linked allelic variation in the gene encoding MAP6/STOP (microtubule-associated protein 6) to schizophrenia, along with altered MAP6/STOP protein expression in the schizophrenic brain and schizophrenic-like behaviors in Map6-deficient mice. In this study, for the first time, we reveal significant decreases in hippocampal Becn1 mRNA and reversal by NAP but not by the antipsychotic clozapine (CLZ) in Map6-deficient (Map6+/−) mice. Normalization of Becn1 expression by NAP was coupled with behavioral protection against hyperlocomotion and cognitive deficits measured in the object recognition test. CLZ reduced hyperlocomotion below control levels and did not significantly affect object recognition. The combination of CLZ and NAP resulted in normalized outcome behaviors. Phase II clinical studies have shown NAP-dependent augmentation of functional activities of daily living coupled with brain protection. The current studies provide a new mechanistic pathway and a novel avenue for drug development. PMID:25484074

  12. Improving the photocatalytic activity and anti-photocorrosion of semiconductor ZnO by coupling with versatile carbon.

    PubMed

    Han, Chuang; Yang, Min-Quan; Weng, Bo; Xu, Yi-Jun

    2014-08-28

    Coupling ZnO with carbon materials using a suitable integration method to form ZnO-carbon composites has been established as a promising strategy to ameliorate the photocatalytic performance of semiconductor ZnO. In this perspective article, we describe the recent advances and current status of enhancing the photocatalytic activity and anti-photocorrosion of semiconductor ZnO by coupling with versatile carbon materials, e.g., C60, carbon nanotube, graphene and other carbon materials. The primary roles of carbon materials in boosting the photoactivity and photostability of ZnO have been outlined and illustrated with some selected typical examples. In particular, the three main kinds of mechanisms with regard to anti-photocorrosion of ZnO by coupling with carbon have been demonstrated. Finally, we give a concise perspective on this important research area and specifically propose further research opportunities in optimizing the photocatalytic performance of ZnO-carbon composites and widening the scope of their potential photocatalytic applications. PMID:25012572

  13. New horizons in schizophrenia treatment: autophagy protection is coupled with behavioral improvements in a mouse model of schizophrenia.

    PubMed

    Merenlender-Wagner, Avia; Shemer, Zeev; Touloumi, Olga; Lagoudaki, Roza; Giladi, Eliezer; Andrieux, Annie; Grigoriadis, Nikolaos C; Gozes, Illana

    2014-01-01

    Autophagy plays a key role in the pathophysiology of schizophrenia as manifested by a 40% decrease in BECN1/Beclin 1 mRNA in postmortem hippocampal tissues relative to controls. This decrease was coupled with the deregulation of the essential ADNP (activity-dependent neuroprotector homeobox), a binding partner of MAP1LC3B/LC3B (microtubule-associated protein 1 light chain 3 β) another major constituent of autophagy. The drug candidate NAP (davunetide), a peptide fragment from ADNP, enhanced the ADNP-LC3B interaction. Parallel genetic studies have linked allelic variation in the gene encoding MAP6/STOP (microtubule-associated protein 6) to schizophrenia, along with altered MAP6/STOP protein expression in the schizophrenic brain and schizophrenic-like behaviors in Map6-deficient mice. In this study, for the first time, we reveal significant decreases in hippocampal Becn1 mRNA and reversal by NAP but not by the antipsychotic clozapine (CLZ) in Map6-deficient (Map6(+/-)) mice. Normalization of Becn1 expression by NAP was coupled with behavioral protection against hyperlocomotion and cognitive deficits measured in the object recognition test. CLZ reduced hyperlocomotion below control levels and did not significantly affect object recognition. The combination of CLZ and NAP resulted in normalized outcome behaviors. Phase II clinical studies have shown NAP-dependent augmentation of functional activities of daily living coupled with brain protection. The current studies provide a new mechanistic pathway and a novel avenue for drug development. PMID:25484074

  14. An improved quasi-diabatic representation of the 1, 2, 3(1)A coupled adiabatic potential energy surfaces of phenol in the full 33 internal coordinates.

    PubMed

    Zhu, Xiaolei; Malbon, Christopher L; Yarkony, David R

    2016-03-28

    In a recent work we constructed a quasi-diabatic representation, H(d), of the 1, 2, 3(1)A adiabatic states of phenol from high level multireference single and double excitation configuration interaction electronic structure data, energies, energy gradients, and derivative couplings. That H(d) accurately describes surface minima, saddle points, and also regions of strong nonadiabatic interactions, reproducing the locus of conical intersection seams and the coordinate dependence of the derivative couplings. The present work determines the accuracy of H(d) for describing phenol photodissociation. Additionally, we demonstrate that a modest energetic shift of two diabats yields a quantifiably more accurate H(d) compared with experimental energetics. The analysis shows that in favorable circumstances it is possible to use single point energies obtained from the most reliable electronic structure methods available, including methods for which the energy gradients and derivative couplings are not available, to improve the quality of a global representation of several coupled potential energy surfaces. Our data suggest an alternative interpretation of kinetic energy release measurements near λphot ∼ 248 nm. PMID:27036453

  15. An improved quasi-diabatic representation of the 1, 2, 31A coupled adiabatic potential energy surfaces of phenol in the full 33 internal coordinates

    NASA Astrophysics Data System (ADS)

    Zhu, Xiaolei; Malbon, Christopher L.; Yarkony, David R.

    2016-03-01

    In a recent work we constructed a quasi-diabatic representation, Hd, of the 1, 2, 31A adiabatic states of phenol from high level multireference single and double excitation configuration interaction electronic structure data, energies, energy gradients, and derivative couplings. That Hd accurately describes surface minima, saddle points, and also regions of strong nonadiabatic interactions, reproducing the locus of conical intersection seams and the coordinate dependence of the derivative couplings. The present work determines the accuracy of Hd for describing phenol photodissociation. Additionally, we demonstrate that a modest energetic shift of two diabats yields a quantifiably more accurate Hd compared with experimental energetics. The analysis shows that in favorable circumstances it is possible to use single point energies obtained from the most reliable electronic structure methods available, including methods for which the energy gradients and derivative couplings are not available, to improve the quality of a global representation of several coupled potential energy surfaces. Our data suggest an alternative interpretation of kinetic energy release measurements near λphot ˜ 248 nm.

  16. PACE Continuous Innovation Indicators—a novel tool to measure progress in cancer treatments

    PubMed Central

    Paddock, Silvia; Brum, Lauren; Sorrow, Kathleen; Thomas, Samuel; Spence, Susan; Maulbecker-Armstrong, Catharina; Goodman, Clifford; Peake, Michael; McVie, Gordon; Geipel, Gary; Li, Rose

    2015-01-01

    Concerns about rising health care costs and the often incremental nature of improvements in health outcomes continue to fuel intense debates about ‘progress’ and ‘value’ in cancer research. In times of tightening fiscal constraints, it is increasingly important for patients and their representatives to define what constitutes ’value’ to them. It is clear that diverse stakeholders have different priorities. Harmonisation of values may be neither possible nor desirable. Stakeholders lack tools to visualise or otherwise express these differences and to track progress in cancer treatments based on variable sets of values. The Patient Access to Cancer care Excellence (PACE) Continuous Innovation Indicators are novel, scientifically rigorous progress trackers that employ a three-step process to quantify progress in cancer treatments: 1) mine the literature to determine the strength of the evidence supporting each treatment; 2) allow users to weight the analysis according to their priorities and values; and 3) calculate Evidence Scores (E-Scores), a novel measure to track progress, based on the strength of the evidence weighted by the assigned value. We herein introduce a novel, flexible value model, show how the values from the model can be used to weight the evidence from the scientific literature to obtain E-Scores, and illustrate how assigning different values to new treatments influences the E-Scores. The Indicators allow users to learn how differing values lead to differing assessments of progress in cancer research and to check whether current incentives for innovation are aligned with their value model. By comparing E-Scores generated by this tool, users are able to visualise the relative pace of innovation across areas of cancer research and how stepwise innovation can contribute to substantial progress against cancer over time. Learning from experience and mapping current unmet needs will help to support a broad audience of stakeholders in their

  17. PACE Continuous Innovation Indicators-a novel tool to measure progress in cancer treatments.

    PubMed

    Paddock, Silvia; Brum, Lauren; Sorrow, Kathleen; Thomas, Samuel; Spence, Susan; Maulbecker-Armstrong, Catharina; Goodman, Clifford; Peake, Michael; McVie, Gordon; Geipel, Gary; Li, Rose

    2015-01-01

    Concerns about rising health care costs and the often incremental nature of improvements in health outcomes continue to fuel intense debates about 'progress' and 'value' in cancer research. In times of tightening fiscal constraints, it is increasingly important for patients and their representatives to define what constitutes 'value' to them. It is clear that diverse stakeholders have different priorities. Harmonisation of values may be neither possible nor desirable. Stakeholders lack tools to visualise or otherwise express these differences and to track progress in cancer treatments based on variable sets of values. The Patient Access to Cancer care Excellence (PACE) Continuous Innovation Indicators are novel, scientifically rigorous progress trackers that employ a three-step process to quantify progress in cancer treatments: 1) mine the literature to determine the strength of the evidence supporting each treatment; 2) allow users to weight the analysis according to their priorities and values; and 3) calculate Evidence Scores (E-Scores), a novel measure to track progress, based on the strength of the evidence weighted by the assigned value. We herein introduce a novel, flexible value model, show how the values from the model can be used to weight the evidence from the scientific literature to obtain E-Scores, and illustrate how assigning different values to new treatments influences the E-Scores. The Indicators allow users to learn how differing values lead to differing assessments of progress in cancer research and to check whether current incentives for innovation are aligned with their value model. By comparing E-Scores generated by this tool, users are able to visualise the relative pace of innovation across areas of cancer research and how stepwise innovation can contribute to substantial progress against cancer over time. Learning from experience and mapping current unmet needs will help to support a broad audience of stakeholders in their efforts to

  18. Integrating mobile technology with routine dietetic practice: the case of myPace for weight management.

    PubMed

    Harricharan, Michelle; Gemen, Raymond; Celemín, Laura Fernández; Fletcher, David; de Looy, Anne E; Wills, Josephine; Barnett, Julie

    2015-05-01

    The field of Mobile health (mHealth), which includes mobile phone applications (apps), is growing rapidly and has the potential to transform healthcare by increasing its quality and efficiency. The present paper focuses particularly on mobile technology for body weight management, including mobile phone apps for weight loss and the available evidence on their effectiveness. Translation of behaviour change theory into weight management strategies, including integration in mobile technology is also discussed. Moreover, the paper presents and discusses the myPace platform as a case in point. There is little clinical evidence on the effectiveness of currently available mobile phone apps in enabling behaviour change and improving health-related outcomes, including sustained body weight loss. Moreover, it is unclear to what extent these apps have been developed in collaboration with health professionals, such as dietitians, and the extent to which apps draw on and operationalise behaviour change techniques has not been explored. Furthermore, presently weight management apps are not built for use as part of dietetic practice, or indeed healthcare more widely, where face-to-face engagement is fundamental for instituting the building blocks for sustained lifestyle change. myPace is an innovative mobile technology for weight management meant to be embedded into and to enhance dietetic practice. Developed out of systematic, iterative stages of engagement with dietitians and consumers, it is uniquely designed to complement and support the trusted health practitioner-patient relationship. Future mHealth technology would benefit if engagement with health professionals and/or targeted patient groups, and behaviour change theory stood as the basis for technology development. Particularly, integrating technology into routine health care practice, rather than replacing one with the other, could be the way forward. PMID:25804507

  19. Which Students Benefit from Self-Paced Mastery Instruction and Why.

    ERIC Educational Resources Information Center

    Stinard, Thomas A.; Dolphin, Warren D.

    1981-01-01

    The determinants of achievement were compared under conventional and self-paced mastery examination schedules in an anatomy/physiology course. General scholastic ability did not interact with method, but prior preparation in science did. Students with less science preparation showed greater achievement under self-paced mastery testing than their…

  20. Web 2.0 and Social Media Connecting Learners in Self-Paced Study: Practitioners' Perspectives

    ERIC Educational Resources Information Center

    Thiessen, Janice

    2016-01-01

    Distance learners determine the time and place for their studies--those engaged in self-paced study may also choose the rate at which they proceed through their courses. However, it is difficult to incorporate purposeful learner-learner interaction into self-paced study. A multiple-case study included three open universities with in-house design…

  1. Age and Self-Selected Performance Pace on a Visual Monitoring Inspection Task.

    ERIC Educational Resources Information Center

    Panek, Paul E.; And Others

    1979-01-01

    Describes various performance measures used in a study to investigate the relation of performance pace to age and information processing ability. Test results indicated no differences in performance pace but differences in performance quality between young and older individuals, with implications for hiring and training older workers. (MF)

  2. Obtaining Technical Assistance. PACE Revised. Level 1. Unit 4. Research & Development Series No. 240AB4.

    ERIC Educational Resources Information Center

    Ashmore, M. Catherine; Pritz, Sandra G.

    This lesson on obtaining technical assistance, the fourth in a series of 18 units, is part of the first level of a comprehensive entrepreneurship curriculum entitled: A Program for Acquiring Competence in Entrepreneurship (PACE). (Designed for use with secondary students, the first level of PACE introduces students to the concepts involved in…

  3. The Relationship between Successful Completion and Sequential Movement in Self-Paced Distance Courses

    ERIC Educational Resources Information Center

    Lim, Janine M.

    2016-01-01

    A course design question for self-paced courses includes whether or not technological measures should be used in course design to force students to follow the sequence intended by the course author. This study examined learner behavior to understand whether the sequence of student assignment submissions in a self-paced distance course is related…

  4. Protecting the Business. PACE Revised. Level 1. Unit 18. Research & Development Series No. 240AB18.

    ERIC Educational Resources Information Center

    Ashmore, M. Catherine; Pritz, Sandra G.

    This unit on protecting a business, the 18th in a series of 18 units, is part of the first level of a comprehensive entrepreneurship curriculum entitled: A Program for Acquiring Competence in Entrepreneurship (PACE). (Designed for use with secondary students, the first level of PACE introduces students to the concepts involved in entrepreneurship…

  5. PACE Instructor Guide. Level 1. Research & Development Series No. 240A.

    ERIC Educational Resources Information Center

    Ashmore, M. Catherine; Pritz, Sandra G.

    This teaching guide is designed for use in implementing the first level of a comprehensive entrepreneurship curriculum entitled: A Program for Acquiring Competence in Entrepreneurship (PACE). Designed for use with secondary students, the first level of PACE consists of 18 lessons that introduce students to the concepts involved in entrepreneurship…

  6. Self-Paced Advanced Individual Training (AIT) and Duty Assignment Procedures.

    ERIC Educational Resources Information Center

    Hunter, Harold; Wagner, Harold

    A study was made to (a) describe how self-paced Military Occupational Specialty (MOS) training affects the Army assignment system; (b) identify ways the existing assignment system can accommodate individualized instruction; and (c) suggest modifications to the assignment system to provide better integration of self-paced training with assignment…

  7. Keeping Pace with K-12 Online & Blended Learning: An Annual Review of Policy and Practice, 2013

    ERIC Educational Resources Information Center

    Watson, John; Murin, Amy; Vashaw, Lauren; Gemin, Butch; Rapp, Chris

    2013-01-01

    This is the 10th annual "Keeping Pace" report. "Keeping Pace" has several goals: (1) add to the body of knowledge about online education policy and practice, and make recommendations for advances; (2) serve as a reference source for information about programs and policies across the country, both for policymakers and…

  8. Effects of Pacing and Cognitive Style across Dynamic and Non-Dynamic Representations

    ERIC Educational Resources Information Center

    Hoffler, Tim N.; Schwartz, Ruth N.

    2011-01-01

    The effects of self-pacing versus system-pacing were examined in different versions of a computer-based learning environment (static pictures/animations). The role of cognitive style was also considered. While the variables investigated did not have a direct impact on either learning outcome or cognitive load, significant interaction effects were…

  9. Locating the Business. PACE Revised. Level 1. Unit 7. Research & Development Series No. 240AB7.

    ERIC Educational Resources Information Center

    Ashmore, M. Catherine; Pritz, Sandra G.

    This lesson on locating a business, the seventh in a series of 18 units, is part of the first level of a comprehensive entrepreneurship curriculum entitled: A Program for Acquiring Competence in Entrepreneurship (PACE). (Designed for use with secondary students, the first level of PACE introduces students to the concepts involved in…

  10. Beyond a Unitary Conception of Pedagogic Pace: Quantitative Measurement and Ethnographic Experience

    ERIC Educational Resources Information Center

    Lefstein, Adam; Snell, Julia

    2013-01-01

    English education policy-makers have targeted classroom time as a key area for regulation and intervention, with "brisk pace" widely accepted as a feature of good teaching practice. We problematise this conventional wisdom through an exploration of objective and subjective dimensions of lesson pace in a corpus of 30 Key Stage 2 literacy lessons…

  11. Child and Parental Outcomes Following Involvement in a Preventive Intervention: Efficacy of the PACE Program

    ERIC Educational Resources Information Center

    Begle, Angela Moreland; Dumas, Jean E.

    2011-01-01

    This study evaluated whether engagement (i.e., attendance and quality of participation) in the Parenting our Children to Excellence (PACE) program predicted positive child and parent outcomes. PACE in an 8-week preventive intervention aimed at parents of preschool children. The study investigated the relation of engagement to outcomes in an…

  12. The femoral route revisited: an alternative for pectoral pacing lead implantation

    PubMed Central

    Bracke, F.A.; Ozdemir, I.; van Gelder, B.

    2010-01-01

    We describe the implantation via the femoral vein of a dual-chamber pacing system with lumenless, catheter-delivered pacing leads in a patient in whom subclavian access on both sides was obstructed. (Neth Heart J 2010;18:42-4.) PMID:20111643

  13. Interaction Equivalency in Self-Paced Online Learning Environments: An Exploration of Learner Preferences

    ERIC Educational Resources Information Center

    Rhode, Jason F.

    2009-01-01

    This mixed methods study explored the dynamics of interaction within a self-paced online learning environment. It used rich media and a mix of traditional and emerging asynchronous computer-mediated communication tools to determine what forms of interaction learners in a self-paced online course value most and what impact they perceive interaction…

  14. PACE: A test bed for the dynamics and control of flexible multibody systems

    NASA Technical Reports Server (NTRS)

    Kwak, Moon K.; Smith, Monty J.; Das, Alok

    1993-01-01

    The Phillips Laboratory at Edwards AFB has constructed a test bed for the validation and comparison of modeling and control theories for the dynamics and control of flexible multibody systems. This project is called the Planar Articulating Controls Experiment (PACE). This paper presents the experimental apparatus for PACE and the problem formulation. An in-depth analysis on DC motor dynamics was also performed.

  15. Development of a Student-Paced Course in General Pathology Utilizing a Computer Managed Evaluation System.

    ERIC Educational Resources Information Center

    Kent, Thomas H.; And Others

    The advantages, feasibility and problems associated with a student-paced course were investigated, and a computer managed evaluation system compared to paper and pencil testing mode. The development of a self-paced course was facilitated by explicit behavior objectives, a variety of learning materials referenced to the objectives and a large pool…

  16. Managing Sales Efforts. PACE Revised. Level 1. Unit 14. Research & Development Series No. 240AB14.

    ERIC Educational Resources Information Center

    Ashmore, M. Catherine; Pritz, Sandra G.

    This lesson on managing sales efforts, the 14th in a series of 18 units, is part of the first level of a comprehensive entrepreneurship curriculum entitled: A Program for Acquiring Competence in Entrepreneurship (PACE). (Designed for use by secondary students, the first level of PACE introduces students to the concepts involved in entrepreneurship…

  17. Managing the Finances. PACE Revised. Level 1. Unit 16. Research & Development Series No. 240AB16.

    ERIC Educational Resources Information Center

    Ashmore, M. Catherine; Pritz, Sandra G.

    This lesson on competent financial management, the 16th in a series of 18 units, is part of the first level of a comprehensive entrepreneurship curriculum entitled: A Program for Acquiring Competence in Entrepreneurship (PACE). (Designed for use with secondary students, the first level of PACE introduces students to the concepts involved in…

  18. Financing the Business. PACE Revised. Level 1. Unit 8. Research & Development Series No. 240AB8.

    ERIC Educational Resources Information Center

    Ashmore, M. Catherine; Pritz, Sandra G.

    This lesson on financing a business, the eighth in a series of 18 units, is part of the first level of a comprehensive entrepreneurship curriculum entitled: A Program for Acquiring Competence in Entrepreneurship (PACE). (Designed for use with secondary students, the first level of PACE introduces students to the concepts involved in…

  19. Safety assessment and biodistribution of povidone as a coating material for cardiac pacing leads

    SciTech Connect

    Jay, M.; Digenis, G.A.

    1983-01-01

    Cardiac pacing leads coated with povidone-(/sup 131/I) were implanted in dogs and the leaching of radioactivity from the leads was monitored by external scintigraphy. The activity which had dissipated from the pacing leads was not as (/sup 131/I)-iodide, but as povidone-(/sup 131/I). Only 50% (mean) of the activity remained on the pacing leads after two weeks while a significant amount of radioactivity was eliminated via urine and feces. The liver was a major site of accumulation of retained activity which had leached off the pacing leads. There was no evidence of large pieces of povidone-(/sup 131/I) in the lungs of the dogs, all of which appeared healthy at the time of sacrifice. The results of this study support the conclusions of a long-term study indicating that povidone is a safe and suitable coating material for pacing leads.

  20. Ab Initio and Improved Empirical Potentials for the Calculation of the Anharmonic Vibrational States and Intramolecular Mode Coupling of N-Methylacetamide

    NASA Technical Reports Server (NTRS)

    Gregurick, Susan K.; Chaban, Galina M.; Gerber, R. Benny; Kwak, Dochou (Technical Monitor)

    2001-01-01

    The second-order Moller-Plesset ab initio electronic structure method is used to compute points for the anharmonic mode-coupled potential energy surface of N-methylacetamide (NMA) in the trans(sub ct) configuration, including all degrees of freedom. The vibrational states and the spectroscopy are directly computed from this potential surface using the Correlation Corrected Vibrational Self-Consistent Field (CC-VSCF) method. The results are compared with CC-VSCF calculations using both the standard and improved empirical Amber-like force fields and available low temperature experimental matrix data. Analysis of our calculated spectroscopic results show that: (1) The excellent agreement between the ab initio CC-VSCF calculated frequencies and the experimental data suggest that the computed anharmonic potentials for N-methylacetamide are of a very high quality; (2) For most transitions, the vibrational frequencies obtained from the ab initio CC-VSCF method are superior to those obtained using the empirical CC-VSCF methods, when compared with experimental data. However, the improved empirical force field yields better agreement with the experimental frequencies as compared with a standard AMBER-type force field; (3) The empirical force field in particular overestimates anharmonic couplings for the amide-2 mode, the methyl asymmetric bending modes, the out-of-plane methyl bending modes, and the methyl distortions; (4) Disagreement between the ab initio and empirical anharmonic couplings is greater than the disagreement between the frequencies, and thus the anharmonic part of the empirical potential seems to be less accurate than the harmonic contribution;and (5) Both the empirical and ab initio CC-VSCF calculations predict a negligible anharmonic coupling between the amide-1 and other internal modes. The implication of this is that the intramolecular energy flow between the amide-1 and the other internal modes may be smaller than anticipated. These results may have

  1. Improved Measurement of 3J(H αi, N i+1 ) Coupling Constants in H 2O Dissolved Proteins

    NASA Astrophysics Data System (ADS)

    Löhr, Frank; Schmidt, Jürgen M.; Maurer, Steffen; Rüterjans, Heinz

    2001-11-01

    A modification to the recently proposed α/β-HN(CO)CA-J TROSY pulse sequence (P. Permi et al., J. Magn. Reson.146, 255-259 (2000)) makes it possible to determine 3J(Hαi, Ni+1) coupling constants from a single E.COSY-type cross-peak pattern rather than from two 1Hα spin-state-edited subspectra. Advantages are increased 15N resolution, critical to extracting accurate 1Hα-15N coupling constants, and minimized differential relaxation due to nested 13Cα and 15N evolution periods. Application of the improved pulse sequence to Desulfovibrio vulgaris flavodoxin results in 3J(Hαi, Ni+1) values being systematically larger than those obtained with the original scheme. Parametrization of the coupling dependence on the protein backbone torsion angle ψ yields the Karplus relation 3J(Hαi, Ni+1)=-1.00 cos2(ψ-120°)+0.65 cos(ψ-120°)-0.15 Hz, with a residual root-mean-square difference of 0.13 Hz between measured and back-calculated coupling constants. The curve compares with data derived from ubiquitin (A. C. Wang and A. Bax, J. Am. Chem. Soc.117, 1810-1813 (1995)), although spanning a slightly larger range of J values in flavodoxin. The orientation of the Ala39/Ser40 peptide link, forming a type-II β-turn in flavodoxin, is twisted against X-ray-derived torsions by approximately 10° in the NMR structure as evident from the analysis of φ- and ψ-related 3J coupling constants. The remaining deviation of some experimental values from the prediction is likely to be due to strong hydrogen bonding, substituent effects, or the additional dependence on the adjacent torsions φ.

  2. A two-dimensional coupled flow-mass transport model based on an improved unstructured finite volume algorithm.

    PubMed

    Zhou, Jianzhong; Song, Lixiang; Kursan, Suncana; Liu, Yi

    2015-05-01

    A two-dimensional coupled water quality model is developed for modeling the flow-mass transport in shallow water. To simulate shallow flows on complex topography with wetting and drying, an unstructured grid, well-balanced, finite volume algorithm is proposed for numerical resolution of a modified formulation of two-dimensional shallow water equations. The slope-limited linear reconstruction method is used to achieve second-order accuracy in space. The algorithm adopts a HLLC-based integrated solver to compute the flow and mass transport fluxes simultaneously, and uses Hancock's predictor-corrector scheme for efficient time stepping as well as second-order temporal accuracy. The continuity and momentum equations are updated in both wet and dry cells. A new hybrid method, which can preserve the well-balanced property of the algorithm for simulations involving flooding and recession, is proposed for bed slope terms approximation. The effectiveness and robustness of the proposed algorithm are validated by the reasonable good agreement between numerical and reference results of several benchmark test cases. Results show that the proposed coupled flow-mass transport model can simulate complex flows and mass transport in shallow water. PMID:25686488

  3. Coupling Laser Diode Thermal Desorption with Acoustic Sample Deposition to Improve Throughput of Mass Spectrometry-Based Screening.

    PubMed

    Haarhoff, Zuzana; Wagner, Andrew; Picard, Pierre; Drexler, Dieter M; Zvyaga, Tatyana; Shou, Wilson

    2016-02-01

    The move toward label-free screening in drug discovery has increased the demand for mass spectrometry (MS)-based analysis. Here we investigated the approach of coupling acoustic sample deposition (ASD) with laser diode thermal desorption (LDTD)-tandem mass spectrometry (MS/MS). We assessed its use in a cytochrome P450 (CYP) inhibition assay, where a decrease in metabolite formation signifies CYP inhibition. Metabolite levels for 3 CYP isoforms were measured as CYP3A4-1'-OH-midazolam, CYP2D6-dextrorphan, and CYP2C9-4'-OH-diclofenac. After incubation, samples (100 nL) were acoustically deposited onto a stainless steel 384-LazWell plate, then desorbed by an infrared laser directly from the plate surface into the gas phase, ionized by atmospheric pressure chemical ionization (APCI), and analyzed by MS/MS. Using this method, we achieved a sample analysis speed of 2.14 s/well, with bioanalytical performance comparable to the current online solid-phase extraction (SPE)-based MS method. An even faster readout speed was achieved when postreaction sample multiplexing was applied, where three reaction samples, one for each CYP, were transferred into the same well of the LazWell plate. In summary, LDTD coupled with acoustic sample deposition and multiplexing significantly decreased analysis time to 0.7 s/sample, making this MS-based approach feasible to support high-throughput screening (HTS) assays. PMID:26420787

  4. Improved feedback control of wall stabilized kink modes with different plasma-wall couplings and mode rotation

    NASA Astrophysics Data System (ADS)

    Peng, Q.; Levesque, J. P.; Stoafer, C. C.; Bialek, J.; Byrne, P.; Hughes, P. E.; Mauel, M. E.; Navratil, G. A.; Rhodes, D. J.

    2016-04-01

    A new algorithm for feedback control of rotating, wall-stabilized kink modes in the High Beta Tokamak-Extended Pulse (HBT-EP) device maintains an accurate phase shift between the perturbation and the measured rotating mode through current control, with control power emphasizing fast rotation and phase jumps over fast amplitude changes. In HBT-EP, wall-stabilized kink modes become unstable above the ideal wall stability limit, and feedback suppression is aimed at delaying the onset of discharge disruption through reduction of the kink mode amplitude. Performance of the new feedback algorithm is tested under different experimental conditions, including variation of the plasma-wall coupling, insertion of a ferritic wall, changing mode rotation frequency over the range of 4-8 kHz using an internal biased electrode, and adjusting the feedback phase-angle to accelerate, amplify, or suppress the mode. We find the previously reported excitation of the slowly rotating mode at high feedback gain in HBT-EP is mitigated by the current control scheme. We also find good agreement between the observed and predicted changes to the mode rotation frequency and amplitude. When ferritic material is introduced, or the plasma-wall coupling becomes weaker as the walls are retracted from plasma, the feedback gain needs to be increased to achieve the same level of suppression. When mode rotation is slowed by a biased electrode, the feedback system still achieves mode suppression, and demonstrates wide bandwidth effectiveness.

  5. Dual chamber pacing: how many patients remain in DDD mode over the long term?

    PubMed Central

    Ibrahim, B.; Sanderson, J. E.; Wright, B.; Palmer, R.

    1995-01-01

    OBJECTIVE--DDD pacing is better than VVI pacing in complete heart block and sick sinus syndrome but is more expensive and demanding. In addition, some patients have to be programmed out of DDD mode and this may have an important impact on the cost-effectiveness of DDD pacing. The purpose of this study was to determine how many patients remain in DDD mode over the long term (up to 10 years). DESIGN--A retrospective analysis of the outcome over 10 years of consecutive patients who had their pacemakers programmed initially in DDD mode. SETTING--A district general hospital. PATIENTS--249 patients with DDD pacemakers. Sixty two patients (24.9%) had predominantly sick sinus syndrome and 180 (72.3%) had predominantly atrioventricular conduction disease. Mean (range) complete follow up for this group of patients was 32 months (1-10 years). RESULTS--Cumulative survival of DDD mode was 83.5% at 60 months. Atrial fibrillation was the commonest reason for abandonment of DDD pacing. Atrial fibrillation developed in 30 patients (12%), with atrial flutter in three (1.2%). Loss of atrial sensing or pacing, pacemaker mediated tachycardia, and various other reasons accounted for reprogramming out of DDD mode in eight patients (3.2%). Overall, an atrial pacing mode was maintained in 91% and VVI pacing was needed in only 9%. CONCLUSIONS--With careful use of programming facilities and appropriate secondary intervention, most patients with dual chamber pacemakers can be maintained successfully in DDD or an alternative atrial pacing mode until elective replacement, although atrial arrhythmia remains a significant problem. There are no good reasons, other than cost, for not using dual chamber pacing routinely as suggested by recent guidelines and this policy can be achieved successfully in a district general hospital pacing centre. PMID:7662461

  6. Coupling a land-surface model with a crop growth model to improve ET flux estimations in the Upper Ganges basin, India

    NASA Astrophysics Data System (ADS)

    Tsarouchi, G. M.; Buytaert, W.; Mijic, A.

    2014-10-01

    Land-Surface Models (LSMs) are tools that represent energy and water flux exchanges between land and the atmosphere. Although much progress has been made in adding detailed physical processes into these models, there is much room left for improved estimates of evapotranspiration fluxes, by including a more reasonable and accurate representation of crop dynamics. Recent studies suggest a strong land-surface-atmosphere coupling over India and since this is one of the most intensively cultivated areas in the world, the strong impact of crops on the evaporative flux cannot be neglected. In this study we dynamically couple the LSM JULES with the crop growth model InfoCrop. JULES in its current version (v3.4) does not simulate crop growth. Instead, it treats crops as natural grass, while using prescribed vegetation parameters. Such simplification might lead to modelling errors. Therefore we developed a coupled modelling scheme that simulates dynamically crop development and parametrized it for the two main crops of the study area, wheat and rice. This setup is used to examine the impact of inter-seasonal land cover changes in evapotranspiration fluxes of the Upper Ganges River basin (India). The sensitivity of JULES with regard to the dynamics of the vegetation cover is evaluated. Our results show that the model is sensitive to the changes introduced after coupling it with the crop model. Evapotranspiration fluxes, which are significantly different between the original and the coupled model, are giving an approximation of the magnitude of error to be expected in LSMs that do not include dynamic crop growth. For the wet season, in the original model, the monthly Mean Error ranges from 7.5 to 24.4 mm month-1, depending on different precipitation forcing. For the same season, in the coupled model, the monthly Mean Error's range is reduced to 5.4-11.6 mm month-1. For the dry season, in the original model, the monthly Mean Error ranges from 10 to 17 mm month-1, depending on

  7. Coupling a land surface model with a crop growth model to improve ET flux estimations in the Upper Ganges basin, India

    NASA Astrophysics Data System (ADS)

    Tsarouchi, G. M.; Buytaert, W.; Mijic, A.

    2014-06-01

    Land surface models are tools that represent energy and water flux exchanges between land and the atmosphere. Although much progress has been made in adding detailed physical processes into these models, there is much room left for improved estimates of evapotranspiration fluxes, by including a more reasonable and accurate representation of crop dynamics. Recent studies suggest a strong land surface-atmosphere coupling over India and since this is one of the most intensively cultivated areas in the world, the strong impact of crops on the evaporative flux cannot be neglected. In this study we dynamically couple the land surface model JULES with the crop growth model InfoCrop. JULES in its current version does not simulate crop growth. Instead, it treats crops as natural grass, while using prescribed vegetation parameters. Such simplification might lead to modelling errors. Therefore we developed a coupled modelling scheme that simulates dynamically crop development and parameterised it for the two main crops of the study area, wheat and rice. This setup is used to examine the impact of inter-seasonal land cover changes in evapotranspiration fluxes of the Upper Ganges river basin (India). The sensitivity of JULES with regard to the dynamics of the vegetation cover is evaluated. Our results show that the model is sensitive to the changes introduced after coupling it with the crop model. Evapotranspiration fluxes, which are significantly different between the original and the coupled model, are giving an approximation of the magnitude of error to be expected in LSMs that do not include dynamic crop growth. For the wet season, in the original model, the monthly Mean Error ranges from 7.5 to 24.4 mm m-1, depending on different precipitation forcing. For the same season, in the coupled model, the monthly Mean Error's range is reduced to 7-14 mm m-1. For the dry season, in the original model, the monthly Mean Error ranges from 10 to 17 mm m-1, depending on different

  8. Pacing, Forcing, or Chance? Milankovitch Plays Dice and Scores Ice Ages. (Invited)

    NASA Astrophysics Data System (ADS)

    Mix, A. C.

    2010-12-01

    Understanding the role of orbital forcing in the ice ages has now occupied paleoclimatologists and paleoceanographers for many decades, and still we don’t really know how this works. Are ice ages directly forced by orbits, or are orbits a pacemaker that organize ice-age oscillations that would occur anyway (i.e., in the absence of orbital forcing)? Tuning of marine d18O (and other) records gives plausibly satisfying results in many contexts, but radiometric dates have led some to suggest that that glacial terminations can precede presumed forcing, and thus must be independent of, or at least only very weakly coupled to, Earth’s orbital variations. Several early efforts sought to separate the background variability and organized orbital pacing of ice ages, and concluded that a large fraction of climate change is stochastic. Simple models of various types imply that thresholds and limits must exist within the glacial system. Combining these ideas of stochasticity and thresholds implies that the timing of glacial-interglacial transition must be to some extent indeterminate, and if so the precise dating of any particular event is not important to defining the orbital controls of climate. Instead the overall pattern of variation in multiple parts of the climate system, if sufficiently constrained in a sequence, may provide better insights.

  9. Low-Sodium DASH Diet Improves Diastolic Function and Ventricular-Arterial Coupling in Hypertensive Heart Failure with Preserved Ejection Fraction

    PubMed Central

    Hummel, Scott L.; Seymour, E. Mitchell; Brook, Robert D.; Sheth, Samar S.; Ghosh, Erina; Zhu, Simeng; Weder, Alan B.; Kovács, Sándor J.; Kolias, Theodore J.

    2014-01-01

    Background Heart failure with preserved ejection fraction (HFPEF) involves failure of cardiovascular reserve in multiple domains. In HFPEF animal models, dietary sodium restriction improves ventricular and vascular stiffness and function. We hypothesized that the sodium-restricted Dietary Approaches to Stop Hypertension diet (DASH/SRD) would improve left ventricular diastolic function, arterial elastance, and ventricular-arterial (V-A) coupling in hypertensive HFPEF. Methods and Results Thirteen patients with treated hypertension and compensated HFPEF consumed the DASH/SRD (target sodium 50 mmol/2100 kcal) for 21 days. We measured baseline and post-DASH/SRD brachial and central BP (via radial arterial tonometry), and cardiovascular function with echocardiographic measures (all previously invasively validated). Diastolic function was quantified via the Parametrized Diastolic Filling formalism, which yields relaxation/viscoelastic (c) and passive/stiffness (k) constants through analysis of Doppler mitral inflow velocity (E-wave) contours. Effective arterial elastance (Ea) end-systolic elastance (Ees), and V-A coupling (defined as the ratio Ees:Ea) were determined using previously published techniques. Wilcoxon matched-pairs tests were used for pre-post comparisons. The DASH/SRD reduced clinic and 24-hour brachial systolic pressure (155±35 to 138±30 and 130±16 to 123±18 mmHg, both p=.02) and central end-systolic pressure trended lower (116±18 to 111±16 mmHg, p=.12). In conjunction, diastolic function improved (c, 24.3±5.3 to 22.7±8.1 s−1;p=.03; k, 252±115 to 170±37 s−1;p=.03), Ea decreased (2.0±0.4 to 1.7±0.4 mmHg/ml;p=.007), and V-A coupling improved (Ees:Ea, 1.5±0.3 to 1.7±0.4;p=.04). Conclusions In hypertensive HFPEF patients, the sodium-restricted DASH diet was associated with favorable changes in ventricular diastolic function, arterial elastance, and V-A coupling. PMID:23985432

  10. Modeling Floodplain Dynamics: Can the Ganges-Brahmaputra Delta keep pace with 21st Century Sea Level Rise?

    NASA Astrophysics Data System (ADS)

    Rogers, K. G.; Overeem, I.

    2013-12-01

    The low-lying Ganges-Brahmaputra (G-B) Delta in Bangladesh is densely populated (~1200 people/km2) and could be flooded within the next century by rapid sea level rise and increased monsoonal rains. The G-B Rivers currently transport 1*109 tons of sediment from their basins in the Himalaya Mountains to the delta each year, with ~90% of the annual sediment load delivered during the Asian summer monsoon. Sediment distribution across the delta's surface by floods and coastal storms has kept pace with the rate of relative sea level rise along the Bengal coast, enabling the delta to maintain a positive elevation. However, ensemble Community Climate System Model experiments predict 11% higher monsoonal rainfall for the next century, potentially leading to extreme flooding events in the delta. Stratigraphic reconstructions show that sedimentation in the upper G-B floodplain was more than doubled under the Early Holocene enhanced monsoonal regime, suggesting that the delta may withstand an increase in monsoon intensity, flooding, and tropical cyclones that are currently predicted. Whether the G-B floodplains and coastal areas will ultimately drown under predicted sea level rise and monsoon intensification depends on a balance of aggradation, eustatic sea level rise and subsidence. To improve predictions of climatic forcing on aggradation rates in the lower G-B floodplain and coastal plain, direct sedimentation measurements collected in 2008 and 2012 in the lower delta are paired with a series of model components coupled within the Community Surface Dynamics Modeling System (CSDMS) Modeling Tool (CMT). We use three separate numerical models to simulate river basin sediment flux, floodplain sedimentation, and tidal-plain aggradation. The model inputs are based on available 20Th century climate and river gauge data, and outputs are compared to modern sedimentation rates within the G-B tidal delta and highly cultivated central coastal plain. The models are then used to test

  11. Endogenous angiotensin-(1-7)/Mas receptor/NO pathway mediates the cardioprotective effects of pacing postconditioning.

    PubMed

    Abwainy, Ala'a; Babiker, Fawzi; Akhtar, Saghir; Benter, Ibrahim F

    2016-01-01

    The aim of the present study was to investigate the role of the ANG-(1-7) receptor (Mas) and nitric oxide (NO) in pacing postconditiong (PPC)-mediated cardioprotection against ischemia-reperfusion injury. Cardiac contractility and hemodynamics were assessed using a modified Langendorff system, cardiac damage was assessed by measuring infarct size and creatinine kinase levels, and levels of phosphorylated and total endothelial NO synthase (eNOS) were determined by Western blot analysis. Isolated hearts were subjected to 30 min of regional ischemia, produced by fixed position ligation of the left anterior descending coronary artery, followed by 30 min of reperfusion (n = 6). Hearts were also subjected to PPC (three cycles of 30 s of left ventricular pacing alternated with 30 s of right atrial pacing) and/or treated during reperfusion with ANG-(1-7), N(G)-nitro-l-arginine methyl ester, or the Mas antagonist (d-Ala7)-ANG I/II (1-7). The PPC-mediated improvement in cardiac contractility and hemodyanamics, cardiac damage, and eNOS phosphorylation were significantly attenuated upon treatment with (d-Ala7)-ANG I/II (1-7) or N(G)-nitro-l-arginine methyl ester. Treatment with ANG-(1-7) improved cardiac function and reduced infarct size and creatinine kinase levels; however, the effects of ANG-(1-7) were not additive with PPC. In conclusion, these data provide novel insights into the cardioprotective mechanisms of PPC in that they involve the Mas receptor and eNOS and further suggest a potential therapeutic role for ANG-(1-7) in cardiac ischemic injury. PMID:26519026

  12. A Sliding Mode Controller Using Nonlinear Sliding Surface Improved With Fuzzy Logic: Application to the Coupled Tanks System

    NASA Astrophysics Data System (ADS)

    Boubakir, A.; Boudjema, F.; Boubakir, C.

    2008-06-01

    This paper proposes an approach of hybrid control that is based on the concept of combining fuzzy logic and the methodology of sliding mode control (SMC). In the present works, a first-order nonlinear sliding surface is presented, on which the developed control law is based. Mathematical proof for the stability and convergence of the system is presented. In order to reduce the chattering in sliding mode control, a fixed boundary layer around the switch surface is used. Within the boundary layer, since the fuzzy logic control is applied, the chattering phenomenon, which is inherent in a sliding mode control, is avoided by smoothing the switch signal. Outside the boundary, the sliding mode control is applied to driving the system states into the boundary layer. Experimental studies carried out on a coupled Tanks system indicate that the proposed fuzzy sliding mode control (FSMC) is a good candidate for control applications.

  13. The Potential of Soft Soil Improvement Through a Coupled Technique Between Electro Kinetic and Alkaline Activation of Soft Soil

    NASA Astrophysics Data System (ADS)

    Ahmed, G. E.; Ismail, H. B.; Huat, B. K.; Afshin, A.; Azhar, A. T. S.

    2016-07-01

    Soil stabilization techniques have been in development for decades with different rates of success. Alkaline activation of soft soil is one of those techniques that has proved to deliver some of the best shear strength values with minor drawbacks in comparison with conventional soil stabilization methods. However, environmental considerations have not been taken into account, as major mineral glassy phase activators are poisoning alkaline solutions, such as sodium-, potassium-hydroxide, and sodium-, potassium-silicate, which poses serious hazards to man and environment. This paper addresses the ways of discarding the involvement of the aforementioned alkaline solutions in soft soil stabilization by investigating the potential of a coupled electro kinetic alkaline activation technique for soft soil strengthening, through which the provision of alkaline pH is governed by electro kinetic potential. Uncertainties in regard to the dissolution of aluminosilicate as well as the dominance of acidic front are challenges that need to be overcome.

  14. Improving the WRF model's simulation over sea ice surface through coupling with a complex thermodynamic sea ice model

    NASA Astrophysics Data System (ADS)

    Yao, Y.; Huang, J.; Luo, Y.; Zhao, Z.

    2015-12-01

    Sea ice plays an important role in the air-ice-ocean interaction, but it is often represented simply in many regional atmospheric models. The Noah sea ice model, which has been widely used in the Weather Research and Forecasting (WRF) model, exhibits cold bias in simulating the Arctic sea ice temperature when validated against the Surface Heat Budget of the Arctic Ocean (SHEBA) in situ observations. According to sensitivity tests, this bias is attributed not only to the simulation of snow depth and turbulent fluxes but also to the heat conduction within snow and ice. Compared with the Noah sea ice model, the high-resolution thermodynamic snow and ice model (HIGHTSI) has smaller bias in simulating the sea ice temperature. HIGHTSI is further coupled with the WRF model to evaluate the possible added value from better resolving the heat transport and solar penetration in sea ice from a complex thermodynamic sea ice model. The cold bias in simulating the surface temperature over sea ice in winter by the original Polar WRF is reduced when HIGHTSI rather than Noah is coupled with the WRF model, and this also leads to a better representation of surface upward longwave radiation and 2 m air temperature. A discussion on the impact of specifying sea ice thickness in the WRF model is presented. Consistent with previous research, prescribing the sea ice thickness with observational information would result in the best simulation among the available methods. If no observational information is available, using an empirical method based on the relationship between sea ice concentration and sea ice thickness could mimic the large-scale spatial feature of sea ice thickness. The potential application of a thermodynamic sea ice model in predicting the change in sea ice thickness in a RCM is limited by the lack of sea ice dynamic processes in the model and the coarse assumption on the initial value of sea ice thickness.

  15. Improved energy coupling into the gain region of the Ni-like Pd transient collisional x-ray laser

    SciTech Connect

    Smith, R; Dunn, J; Filevich, J; Moon, S; Nilsen, J; Keenan, R; Shlyaptsev, V; Rocca, J; Hunter, J; Shepherd, R; Booth, R; Marconi, M

    2004-10-05

    We present within this paper a series of experiments, which yield new observations to further our understanding of the transient collisional x-ray laser medium. We use the recently developed technique of picosecond x-ray laser interferometry to probe the plasma conditions in which the x-ray laser is generated and propagates. This yields two dimensional electron density maps of the plasma taken at different times relative to the peak of the 600ps plasma-forming beam. In another experimental campaign, the output of the x-ray laser plasma column is imaged with a spherical multilayer mirror onto a CCD camera to give a two-dimensional intensity map of the x-ray laser output. Near-field imaging gives insights into refraction, output intensity and spatial mode structure. Combining these images with the density maps gives an indication of the electron density at which the x-ray laser is being emitted at (yielding insights into the effect of density gradients on beam propagation). Experimental observations coupled with simulations predict that most effective coupling of laser pump energy occurs when the duration of the main heating pulse is comparable to the gain lifetime ({approx}10ps for Ni-like schemes). This can increase the output intensity by more than an order of magnitude relative to the case were the same pumping energy is delivered within a shorter heating pulse duration (< 3ps). We have also conducted an experiment in which the output of the x-ray laser was imaged onto the entrance slit of a high temporal resolution streak camera. This effectively takes a one-dimensional slice of the x-ray laser spatial profile and sweeps it in time. Under some conditions we observe rapid movement of the x-ray laser ({approx} 3 {micro}m/ps) towards the target surface.

  16. Cardiac response induced by voluntary self-paced finger movement.

    PubMed

    Florian, G; Stancák, A; Pfurtscheller, G

    1998-05-01

    Cardiac responses induced by slow and brisk voluntary self-paced index finger movements of the dominant and non-dominant hand were investigated in a group of 12 right-handed subjects. Since subjects synchronised movement and respiration, initiating movement preferably during inspiration, a novel method of evaluating the movement-induced cardiac response was used. This method allows one to distinguish the differential effects on the cardiac response due to movement and respiration. The effect of type of movements (slow vs. brisk) and hand (right vs. left) were analysed. Slow movements induced a monophasic cardiac response, consisting of cardiac deceleration preceding and accompanying movement. Brisk movements induced a biphasic cardiac response, consisting of preparatory deceleration followed by slight post-movement cardiac acceleration. Hand-dominance did not influence the movement-induced cardiac response. The results suggest that neocortical structures involved in planning and execution of voluntary movement impinge upon brainstem cardiovascular nuclei. Vagal cardiac outflow is affected and gives rise to movement-induced changes in cardiac chronotropism. PMID:9545662

  17. Augmented preexcitation assessed by scintigraphic phase analysis during atrial pacing

    SciTech Connect

    Botvinick, E.; Dae, M.W.; Scheinman, M.; Davis, J.; Schechtmann, N.; O'Connell, W.; Faulkner, D.; Iskikian, J.

    1985-05-01

    To assess the ability of phase analysis to demonstrate changes in the degrees of preexcitation(P), blood pool scintigraphy was performed at rest and with atrial pacing(AP) in 9 patients(PTS) with WPW and normal ventricular function. There were 6 PTS with left lateral and 3 with right lateral bypass pathways(BP) confirmed on electrophysiologic study(EPS). In 6 PTS with minimal P at rest, ventricular phase patterns were symmetrical and earliest phase single(PA) occurred simultaneously in the septum and at the site of the BP. The site of earliest PA in the remaining PTS occurred at the BP with a difference in mean ventricular PA of 5.2/sup 0/. Additionally, PA moved the site of latest PA the site of ''fusion,'' away from the BP again consistent with augmented P, and widened the QRS complex from a mean of .10 to .12 secs. Phase analysis can demonstrate dynamic changes in the level of P and may complement EPS in the evaluation of these disorders.

  18. Does an auditory distractor sequence affect self-paced tapping?

    PubMed

    Repp, Bruno H

    2006-01-01

    This study investigated whether an auditory distractor (D) sequence affects the timing of self-paced finger tapping. To begin with, Experiment 1 replicated earlier findings by showing that, when taps are synchronized with an isochronous auditory target (T) sequence, an isochronous D sequence of different tempo and pitch systematically modulates the tap timing. The extent of the modulation depended on the relative intensity of the T and D tones, but not on their pitch distance. Experiment 2 then used a synchronization-continuation paradigm in which D sequences of different tempi were introduced only during continuation tapping. Although the D sequences rarely captured the taps completely, they did increase the tapping variability and deviations from the correct tempo. Furthermore, they eliminated the negative correlation between successive inter-tap intervals and led to intermittent phase locking when the tapping period was close to the period of the D sequence. These distractor effects occurred regardless of whether or not the taps generated auditory feedback tones. The distractor effects thus depend neither on the intention to synchronize with a T sequence nor on the simultaneous perception of two auditory sequences. Rather, they seem to reflect a basic attraction of rhythmic movement to auditory rhythms. PMID:16098944

  19. Factors affecting the heart rate during self-paced walking.

    PubMed

    Bassey, E J; Macdonald, I A; Patrick, J M

    1982-01-01

    The results of 277 self-paced walking tests have been analysed for the effects of body composition, sex and age using step-up multiple regression analysis. Equations are given for the influence of the significant factors on chosen walking speeds and on heart rate (fc) (standardised at 4.8 km . h-1 by interpolation from points recorded at three walking speeds). The basic equations are: Normal speed (km . h-1) = 1.72 + 2.13 stature (m) - 0.008 age (years) Fast speed (km . h-1) = 0.54 + 3.69 stature (m) - 0.016 age (years) For men: fc4.8 (beat . min-1) = 161 - 50.7 stature (m) + 0.223 body weight (kg) For women: fc4.8 (beat . min-1) = 161 - 50.7 stature (m) + 0.223 body weight (kg) + 4.43 The significant factors affecting freely chosen walking speeds are stature and age. When estimates of body composition are available, percentage fat is found to be the most influential single factor affecting fc, while sex no longer has a significant effect, and age now has a negative influence. When allowance is made for these factors the effects of customary physical activity can be seen more clearly. PMID:7199445

  20. Electrical Pacing of Cardiac Tissue Including Potassium Inward Rectification

    PubMed Central

    Galappaththige, Suran; Roth, Bradley J.

    2015-01-01

    In this study cardiac tissue is stimulated electrically through a small unipolar electrode. Numerical simulations predict that around an electrode are adjacent regions of depolarization and hyperpolarization. Experiments have shown that during pacing of resting cardiac tissue the hyperpolarization is often inhibited. Our goal is to determine if the inward rectifying potassium current (IK1) causes the inhibition of hyperpolarization. Numerical simulations were carried out using the bidomain model with potassium dynamics specified to be inward rectifying. In the simulations, adjacent regions of depolarization and hyperpolarization were observed surrounding the electrode. For cathodal currents the virtual anode produces a hyperpolarization that decreases over time. For long duration pulses the current-voltage curve is non-linear, with very small hyperpolarization compared to depolarization. For short pulses, the hyperpolarization is more prominent. Without the inward potassium rectification, the current voltage curve is linear and the hyperpolarization is evident for both long and short pulses. In conclusion, the inward rectification of the potassium current explains the inhibition of hyperpolarization for long duration stimulus pulses, but not for short duration pulses. PMID:26057242

  1. Piston designs keep pace with increased engine performance

    SciTech Connect

    Mullins, P.

    1996-12-01

    Piston technology for medium-speed diesel engines is having to keep pace with steadily increasing engine performance criteria. Specific output of medium-speed diesel engines has increased some 50% since 1970, according to Walter Griffiths, chief engineer at the UK-based AE Geotze Special Products Ltd. To satisfy the higher performance now required, a two-piece piston has been developed and went into production in 1995. This type still uses an aluminum alloy forged body, but incorporates a steel crown. The composite piston can carry higher engine ratings and resists the abrasive deposits formed by heavy fuel operation. It has become well established for bore sizes above 300 mm and is becoming increasingly specified for engines down to 200 mm. The latest solution to the carbon deposits on the top of the piston that has gained widespread acceptance within the industry is to reduce the diameter of the bore above the top ring and cut back the top land to maintain the normal operating clearance. This requires an insert to be fitted into the liner after the piston has been assembled. The effect is to limit the carbon build-up on the top land to a specific diameter, which is always less than the bore diameter. Thus there is no possibility of top land contact with the bore over the effective stroke of the piston rings. 2 figs.

  2. Paleoclimatology: Second clock supports orbital pacing of the ice ages

    SciTech Connect

    Kerr, R.A.

    1997-05-02

    For a while, it looked as if a water-filled crack in the Nevada desert might doom the accepted explanation of the ice ages. Twenty years ago, the so-called astronomical theory had carried the day. Oceanographers had found evidence implying that the march of ice ages over the last million years was paced by the cyclical stretching and squeezing of Earth`s orbit around the sun, which would have altered the way sunlight fell on the planet`s surface. But in 1988, researchers scuba diving in Nevada`s Devils Hole came up with a climate record--captured in carbonate deposits in the crack-that seemed to contradict this chronology. This article discusses the findings and the puzzles that still remain. The records of sea-level change in Barbados coral appear to be right and the astronomical theory is on solid ground using a new clock based on the radioactive decay of uranium-235 to protactinium-231. However, the Devils Hole record also seems to be correct.

  3. Bioelectromagnetic localization of a pacing catheter in the heart

    NASA Astrophysics Data System (ADS)

    Pesola, K.; Nenonen, J.; Fenici, R.; Lötjönen, J.; Mäkijärvi, M.; Fenici, P.; Korhonen, P.; Lauerma, K.; Valkonen, M.; Toivonen, L.; Katila, T.

    1999-10-01

    The accuracy of localizing source currents within the human heart by non-invasive magneto- and electrocardiographic methods was investigated in 10 patients. A non-magnetic stimulation catheter inside the heart served as a reference current source. Biplane fluoroscopic imaging with lead ball markers was used to record the catheter position. Simultaneous multichannel magnetocardiographic (MCG) and body surface potential mapping (BSPM) recordings were performed during catheter pacing. Equivalent current dipole localizations were computed from MCG and BSPM data, employing standard and patient-specific boundary element torso models. Using individual models with the lungs included, the average MCG localization error was 7±3 mm, whereas the average BSPM localization error was 25±4 mm. In the simplified case of a single homogeneous standard torso model, an average error of 9±3 mm was obtained from MCG recordings. The MCG localization accuracies obtained in this study imply that the capability of multichannel MCG to locate dipolar sources is sufficient for clinical purposes, even without constructing individual torso models from x-ray or from magnetic resonance images.

  4. Coupling landscape water storage and supplemental irrigation to increase productivity and improve environmental stewardship in the US Midwest

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agriculture must expand production for a growing population while simultaneously reducing its environmental impacts. These goals need not be in tension with one another. Here we outline a vision for improving both the productivity and environmental performance of agriculture in the US Corn Belt. Mea...

  5. Derivation of improved load transformation matrices for launchers-spacecraft coupled analysis, and direct computation of margins of safety

    NASA Technical Reports Server (NTRS)

    Klein, M.; Reynolds, J.; Ricks, E.

    1989-01-01

    Load and stress recovery from transient dynamic studies are improved upon using an extended acceleration vector in the modal acceleration technique applied to structural analysis. Extension of the normal LTM (load transformation matrices) stress recovery to automatically compute margins of safety is presented with an application to the Hubble space telescope.

  6. Improving interannual prediction skill in a changing climate via the identi cation of compensating coupled model errors

    SciTech Connect

    Tziperman, Eli; MacMartin, Douglas

    2013-08-31

    Significant progress can be made through a truly interdisciplinary effort, combining the expertise from climate dynamics and from engineering control. We believe that this novel approach can make a unique and valuable contribution, and help the climate community deliver improved models for the potential response of the Earth's climate to increased greenhouse gas levels.

  7. Improved theoretical approximation for the ion drag force in collisionless plasma with strong ion-grain coupling

    SciTech Connect

    Khrapak, S. A.; Nosenko, V.; Morfill, G. E.; Merlino, R.

    2009-04-15

    We point out a deficiency in our previous analytic calculation of the ion drag force for conditions of the experiment by Nosenko et al. [Phys. Plasmas 14, 103702 (2007)]. An inaccurate approximation is corrected and the ion drag force is recalculated. The improved model yields better overall agreement with the experimental results as compared to the original calculation.

  8. patGPCR: A Multitemplate Approach for Improving 3D Structure Prediction of Transmembrane Helices of G-Protein-Coupled Receptors

    PubMed Central

    Wu, Hongjie; Lü, Qiang; Quan, Lijun; Qian, Peide; Xia, Xiaoyan

    2013-01-01

    The structures of the seven transmembrane helices of G-protein-coupled receptors are critically involved in many aspects of these receptors, such as receptor stability, ligand docking, and molecular function. Most of the previous multitemplate approaches have built a “super” template with very little merging of aligned fragments from different templates. Here, we present a parallelized multitemplate approach, patGPCR, to predict the 3D structures of transmembrane helices of G-protein-coupled receptors. patGPCR, which employs a bundle-packing related energy function that extends on the RosettaMem energy, parallelizes eight pipelines for transmembrane helix refinement and exchanges the optimized helix structures from multiple templates. We have investigated the performance of patGPCR on a test set containing eight determined G-protein-coupled receptors. The results indicate that patGPCR improves the TM RMSD of the predicted models by 33.64% on average against a single-template method. Compared with other homology approaches, the best models for five of the eight targets built by patGPCR had a lower TM RMSD than that obtained from SWISS-MODEL; patGPCR also showed lower average TM RMSD than single-template and multiple-template MODELLER. PMID:23554839

  9. Orbitally paced phosphogenesis in Mediterranean shallow marine carbonates during the middle Miocene Monterey event

    NASA Astrophysics Data System (ADS)

    Auer, Gerald; Hauzenberger, Christoph A.; Reuter, Markus; Piller, Werner E.

    2015-04-01

    During the Oligo-Miocene major phases of phosphogenesis occurred in the Earth's oceans. Particularly in the Mediterranean region phosphate-rich sediments are well-known during this time. However, most phosphate-rich beds represent condensed or allochthonous hemipelagic deposits, formed by a complex interplay of physical and chemical enrichment processes. These underlying processes limit the application of these records for the study of a possible Milankovitch-scale climate control on Miocene phosphogenesis. In this regard the middle Miocene "Monterey event" is of particular interest, as it represents a documented phase of phosphogenesis coupled with a prominent carbon isotope excursion containing nine orbitally paced carbon isotope maxima (CM-events). The Oligo-Miocene shallow marine Decontra section located on the Maiella Platform (central Apennines, Italy), is a widely continuous carbonate succession in a mostly outer to middle neritic setting. Of particular interest are the well-winnowed grain- to packstones of the Middle Miocene Bryozoan Limestone, were occurrences of authigenic phosphate grains coincide with the Monterey event. The depositional setting of the Bryozoan Limestone allows to resolve the influence of orbital forcing on phosphogenesis, within a bio-, chemo- and cyclostratigraphically constrained stratigraphic model. LA-ICP-MS analyses revealed a significant enrichment of Uranium in the studied authigenic phosphate grains compared to the surrounding carbonate sediment. Notably, the Uranium enrichment allowed the use of natural gamma radiation (GR) as a proxy for the qualitative estimation of autochthonous phosphate content within the section, based on the absence of any other major gamma ray sources within the sediment. Time series analyses of high-resolution GR data indicate a strong influence of the 405kyr long-eccentricity cycle on natural gamma radiation in the Bryozoan Limestone. Our results link maxima in the GR record and thus phosphate

  10. An improved analysis of coupled multicomponent diffusion of divalent cations in aluminosilicate garnet: An experimental and numerical study

    NASA Astrophysics Data System (ADS)

    Borinski, S. A.; Chakraborty, S.; Hoppe, U.

    2010-12-01

    Garnets in natural rocks show a variety of compositional zoning. These zonings preserve memory of the thermal and growth histories of the minerals which could be retrieved if appropriate cation diffusion data were available. Coupled multicomponent diffusion of major divalent cations in aluminosilicate garnet has been studied experimentally e.g. in [1,2,3]. Diffusion coefficients were retrieved from experimentally induced concentration profiles assuming that (i) garnets behaved thermodynamically ideally at the high temperatures of the experiments and (ii) the convolution effect on microprobe analysis could be approximated by an equation for convolution effect of a profile with a single, constant diffusivity. Further, calculated and measured profiles were matched visually without any statistical criteria. We have now carried out diffusion experiments in a piston cylinder apparatus using diffusion couples made from homogeneous gem quality natural pyrope and almandine garnets. These were annealed within graphite capsules under nominally anhydrous conditions at 25-35 kbar, 1260-1400 °C. The resulting profiles were described by diffusion coefficient matrices that accounted for the effects of thermodynamic non-ideality using the garnet solution model of [4]. Convolution was calculated using a numerical scheme that did not require any assumption of constant D. And finally, results obtained from visual fitting were compared to those obtained by error minimization according to the Nelder-Mead downhill simplex method. We find that the visual and error minimization routines yield diffusion coefficients that are within a factor of two of each other. Further, it is shown that for some compositional ranges it is impossible to constrain tracer diffusion coefficients of certain elements. This needs to be consid-ered in future studies designed to determine diffusion coefficients. The effects of thermodynamic non-ideality and a more exact convolution correction are small, but when

  11. Increased work pace is unprofitable: a beef-cutting case study.

    PubMed

    Vogel, K; Karltun, J; Yeow, P H P; Eklund, J

    2015-07-01

    The beef industry worldwide is showing a trend towards increased cutting pace aimed at higher profits. However, prior research in the duck meat industry suggested that a higher cutting pace reduced quality and yield, leading to losses. This study aimed to test this hypothesis by investigating the effects of varying beef-cutting paces on yield, quality and economy. A field experiment was conducted on six workers cutting beef fillet, sirloin and entrecôte. Three types of paces were sequentially tested: Baseline (i.e., status quo), 'Quantity focus' (i.e., pace required to maximise quantity) and 'Quality focus' (i.e., pace required to minimise errors). The results showed a significant drop in yield, increased rate of quality deficiency and economic losses with the change to 'Quantity focus' (from Baseline and 'Quality focus') for all meat types. Workers supported these results and also added health problems to the list. The results confirmed that an increased cutting pace is unprofitable. PMID:25828161

  12. Cardiomyopathy induced by artificial cardiac pacing: myth or reality sustained by evidence?

    PubMed Central

    Ferrari, Andrés Di Leoni; Borges, Anibal Pires; Albuquerque, Luciano Cabral; Sussenbach, Carolina Pelzer; da Rosa, Priscila Raupp; Piantá, Ricardo Medeiros; Wiehe, Mario; Goldani, Marco Antônio

    2014-01-01

    Implantable cardiac pacing systems are a safe and effective treatment for symptomatic irreversible bradycardia. Under the proper indications, cardiac pacing might bring significant clinical benefit. Evidences from literature state that the action of the artificial pacing system, mainly when the ventricular lead is located at the apex of the right ventricle, produces negative effects to cardiac structure (remodeling, dilatation) and function (dissinchrony). Patients with previously compromised left ventricular function would benefit the least with conventional right ventricle apical pacing, and are exposed to the risk of developing higher incidence of morbidity and mortality for heart failure. However, after almost 6 decades of cardiac pacing, just a reduced portion of patients in general would develop these alterations. In this context, there are not completely clear some issues related to cardiac pacing and the development of this cardiomyopathy. Causality relationships among QRS widening with a left bundle branch block morphology, contractility alterations within the left ventricle, and certain substrates or clinical (previous systolic dysfunction, structural heart disease, time from implant) or electrical conditions (QRS duration, percentage of ventricular stimulation) are still subjecte of debate. This review analyses contemporary data regarding this new entity, and discusses alternatives of how to use cardiac pacing in this context, emphasizing cardiac resynchronization therapy. PMID:25372916

  13. MRI assessment of pacing induced ventricular dyssynchrony in an isolated human heart.

    PubMed

    Eggen, Michael D; Bateman, Michael G; Rolfes, Christopher D; Howard, Stephen A; Swingen, Cory M; Iaizzo, Paul A

    2010-02-01

    This study demonstrates the capabilities of MRI in the assessment of cardiac pacing induced ventricular dyssynchrony, and the findings support the need for employing more physiological pacing. A human donor heart deemed non-viable for transplantation, was reanimated using an MR compatible, four-chamber working perfusion system. The heart was imaged using a 1.5T MR scanner while being paced from the right ventricular apex (RVA) via an epicardial placed lead. Four-chamber, short-axis, and tagged short-axis cines were acquired in order to track wall motion and intramyocardial strain during pacing. The results of this study revealed that the activation patterns of the left ventricle (LV) during RVA pacing demonstrated intraventricular dyssynchrony; as the left ventricular mechanical activation proceeded from the septum and anterior wall to the lateral wall, with the posterior wall being activated last. As such, the time difference to peak contraction between the septum and lateral wall was approximately 125 msec. Likewise, interventricular dyssynchrony was demonstrated from the four-chamber cine as the time difference between the peak LV and RV free wall motion was 180 msec. With the ongoing development of MR safe and MR compatible pacing systems, we can expect MRI to be added to the list of imaging modalities used to optimize cardiac resynchronization therapy (CRT) and/or alternate site pacing. PMID:20099368

  14. Kinematic hand parameters in front crawl at different paces of swimming.

    PubMed

    Samson, Mathias; Monnet, Tony; Bernard, Anthony; Lacouture, Patrick; David, Laurent

    2015-11-01

    The aim of this study was to investigate the evolution of kinematic hand parameters (sweepback angle, angle of attack, velocity, acceleration and orientation of the hand relative to the absolute coordinate system) throughout an aquatic stroke and to study the possible modifications caused by a variation of the swimming pace. Seventeen competitive swimmers swam at long distance, middle distance and sprint paces. Parameters were calculated from the trajectory of seven markers on the hand measured with an optoelectronic system. Results showed that kinematic hand parameters evolve differently depending on the pace. Angle of attack, sweepback angle, acceleration and orientation of the hand do not vary significantly. The velocity of the hand increases when the pace increases, but only during the less propulsive phases (entry and stretch and downsweep to catch). The more the pace increases and the more the absolute durations of the entry and stretch and downsweep to catch phases decrease. Absolute durations of the insweep and upsweep phases remain constant. During these phases, the propulsive hand forces calculated do not vary significantly when the pace increases. The increase of swimming pace is then explained by the swimmer's capacity to maintain propulsive phases rather than increasing the force generation within each cycle. PMID:26433921

  15. The importance of avoiding unnecessary right ventricular pacing in clinical practice

    PubMed Central

    Akerström, Finn; Arias, Miguel A; Pachón, Marta; Jiménez-López, Jesús; Puchol, Alberto; Juliá-Calvo, Justo

    2013-01-01

    Symptomatic bradycardia is effectively treated with the implantation of a cardiac pacemaker. Although a highly successful therapy, during recent years there has been a focus on the negative effects associated with long-term pacing of the apex of the right ventricle (RV). It has been shown in both experimental and clinical studies that RV pacing leads to ventricular dyssynchrony, similar to that of left bundle branch block, with subsequent detrimental effects on cardiac structure and function, and in some cases adverse clinical outcomes such as atrial fibrillation, heart failure and death. There is substantial evidence that patients with reduced left ventricular function (LVEF) are at particular high risk of suffering the detrimental clinical effects of long-term RV pacing. The evidence is, however, incomplete, coming largely from subanalyses of pacemaker and implantable cardiac defibrillator studies. In this group of patients with reduced LVEF and an expected high amount of RV pacing, biventricular pacing (cardiac resynchronization therapy) devices can prevent the negative effects of RV pacing and reduce ventricular dyssynchrony. Therefore, cardiac resynchronization therapy has emerged as an attractive option with promising results and more clinical studies are underway. Furthermore, specific pacemaker algorithms, which minimize RV pacing, can also reduce the negative effects of RV stimulation on cardiac function and may prevent clinical deterioration. PMID:24340139

  16. MRI Assessment of Pacing Induced Ventricular Dyssynchrony in an Isolated Human Heart

    PubMed Central

    Eggen, Michael D.; Bateman, Michael G.; Rolfes, Christopher D.; Howard, Stephen A.; Swingen, Cory M.; Iaizzo, Paul A.

    2010-01-01

    This study demonstrates the capabilities of MR imaging in the assessment of cardiac pacing induced ventricular dyssynchrony, and findings support the need for employing more physiological pacing. A human donor heart deemed non-viable for transplantation, was reanimated using an MR compatible, four-chamber working perfusion system. The heart was imaged using a 1.5T MR scanner while being paced from the right ventricular apex (RVA) via an epicardial placed lead. Four-chamber, short-axis, and tagged short-axis cines were acquired in order track wall motion and intramyocardial strain during pacing. The results of this study revealed that the activation patterns of the left ventricle (LV) during RVA pacing demonstrated intraventricular dyssynchrony; as the left ventricular mechanical activation proceeded from the septum and anterior wall to the lateral wall, with the posterior wall being activated last. As such, the time difference to peak contraction between the septum and lateral wall was ∼125 ms. Likewise, interventricular dyssynchrony was demonstrated from the four-chamber cine as the time difference between the peak LV and RV free wall motion was 180 ms. With the ongoing development of MR safe and MR compatible pacing systems, we can expect MRI to be added to the list of imaging modalities used to optimize cardiac resynchronization therapy and/or alternate site pacing. PMID:20099368

  17. Improvements in Fabrication of 3D SU-8 Prisms for Low-Coupling-Loss Interconnections Between Fibers and Waveguides

    NASA Astrophysics Data System (ADS)

    Nguyen, Minh-Hang; Chu, Thi-Xuan; Nguyen, Long; Nguyen, Hai-Binh; Lee, Chun-Wei; Tseng, Fan-Gang; Chen, Te-Chang; Lee, Ming-Chang

    2016-07-01

    Fabrication of three-dimensional (3D) SU-8 (an epoxy-based negative photoresist from MicroChem) prisms as low-loss couplers for interconnection between optical components, particularly optical fibers and silicon-on-isolator waveguides (SOI WGs), which have mismatched mode sizes, has been investigated. With an interfacial structure formed by a 3D SU-8 prism partly overlaying an SOI WG end with a portion of buried oxide (BOX) removed under the interface, low-loss coupling is ensured and the transmission efficiency can reach 70%. To fabricate these 3D SU-8 prisms, a simple method with two photolithography steps was used for SU-8 hinges and CYTOP (an amorphous fluoropolymer from AGC Chemicals) prism windows, with mild soft and hard bakes, to define the prism profiles with diluted SU-8 filled in the CYTOP prism windows. A buffered oxide etchant is used to remove BOX parts under the interfaces. Some of the fabricated structures were tested, demonstrating the contribution of overlaying SU-8 prisms to the transmission efficiency of optical interconnections between fibers and SOI WGs.

  18. An improved thin-layer chromatography/mass spectrometry coupling using a surface sampling probe electrospray ion trap system

    SciTech Connect

    Ford, Michael J; Van Berkel, Gary J

    2004-01-01

    A combined surface sampling probe/electrospray emitter coupled with an ion trap mass spectrometer was used for the direct read out of unmodified reversed-phase C18 thin-layer chromatography (TLC) plates. The operation of the surface sampling electrospray ionization interface in positive and negative ionization modes was demonstrated through the direct analysis of TLC plates on which a commercial test mix comprised of four dye compounds viz., rhodamine B, fluorescein, naphthol blue black, and fast green FCF, and an extract of the caffeine-containing plant Ilex vomitoria, were spotted and developed. Acquisition of full-scan mass spectra and automated collection of MS/MS product ion spectra while scanning a development lane along the surface of a TLC plate demonstrated the advantages of using an ion trap in this combination. Details of the sampling system, benefits of analyzing a developed lane in both positive ion and negative ion modes, levels of detection while surface scanning, surface scan speed effects, and the utility of three-dimensional data display, are also discussed.

  19. 77 FR 60732 - PACE Select Advisors Trust and UBS Global Asset Management (Americas) Inc.; Notice of Application

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-04

    ... COMMISSION PACE Select Advisors Trust and UBS Global Asset Management (Americas) Inc.; Notice of Application... requirements. The requested order would supersede two prior orders.\\1\\ \\1\\ PaineWebber PACE Select Advisors...) and 21666 (Jan. 11, 1996) (order). Applicants: PACE Select Advisors Trust (the ``Trust'') and...

  20. Factors Affecting the Study Pace of First-Year Law Students: In Search of Study Counselling Tools

    ERIC Educational Resources Information Center

    Haarala-Muhonen, Anne; Ruohoniemi, Mirja; Lindblom-Ylanne, Sari

    2011-01-01

    This study explores factors affecting the study pace of law students during their first academic year. The participants comprised two student groups: those whose number of study credits were the lowest and highest. Altogether, 25 students (11 with a slow and 14 with a fast study pace) were interviewed. The factors affecting study pace mentioned by…